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The Quarterly Journal of Science, Literature and the Arts, July-December, 1827

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Title: The Quarterly Journal of Science, Literature and the Arts, July-December, 1827

Author: Various


        
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*** START OF THE PROJECT GUTENBERG EBOOK THE QUARTERLY JOURNAL OF SCIENCE, LITERATURE AND THE ARTS, JULY-DECEMBER, 1827 ***

 TRANSCRIBER'S NOTE: See Transcriber's Endnote for details of this
 transcription.




 THE
 QUARTERLY JOURNAL
 OF
 SCIENCE,
 LITERATURE, AND ART.

 [Illustration: Royal Institution of Great Britain Emblem.]

 JULY TO DECEMBER, 1827.


 LONDON:

 HENRY COLBURN, NEW BURLINGTON-STREET.

 MDCCCXXVII.




 CONTENTS.
 _July—Oct._ 1827.


 On the Beauties contained in the Ovals and in the elliptic
 Curves, both simple and combined, generated from the same
 Figure or Disk. By R. R. REINAGLE, Esq., R.A. 1

 On the Art of forming Diamonds into Single Lenses for
 Microscopes. By Mr. A. PRITCHARD. 15

 Analysis of a newly-discovered Spring, at Stanley, near
 Wakefield. By Mr. WILLIAM WEST. 21

 Observations on the State of Naval Construction in this
 Country. 25

 On Malaria. No. II. By Dr. MAC CULLOCH, M.D., F.R.S., &c. 39

 Dr. TURNER’s _Elements of Chemistry_, reviewed 60

 Experiments on Audition. Communicated by Mr. C. WHEATSTONE. 67

 On the Petromyzon Marinus 72

 Observations upon the Motion of the Leaves of the Sensitive
 Plant 76

 Experiments on the Nature of LABARRAQUES’ Disinfecting Soda
 Liquid. By M. FARADAY, F.R.S., Cor. Mem. Roy. Acad. Sci.
 Paris, &c. 84

 Hieroglyphical Fragments, with some Remarks on English
 Grammar. In a Letter to Baron William Von HUMBOLDT. By a
 Correspondent 92

 Dr. MAC CULLOCH’s ‘_Malaria; an Essay on the Production and
 Propagation of this Poison_,’ reviewed 100

 Account of a New Genus of Plants, called _Reevesia_. By J.
 LINDLEY, Esq., F.L.S., &c. &c. 109

 ASTRONOMICAL AND NAUTICAL COLLECTIONS.

   i. FRESNEL on the Undulatory Theory of Light 113

   ii. Rule for the Correction of a Lunar Observation. By Mr.
   W. WISEMAN, of Hull 135

 ‘_De l’Influence des Agens Physiques sur la Vie_. Par W. F.
 EDWARDS, D.M.’ &c., reviewed 137

 Account of Professor CARLINI’s Pendulum Experiments on Mont
 Cenis 153

 Analysis of ‘_Transactions of the Horticultural Society_.
 Vol. vii. Part I.’ 159

 _On the Recent Elucidations of Early Egyptian History_ 176

 _Proceedings of the Horticultural Society_. 190

 MISCELLANEOUS INTELLIGENCE.

 I. MECHANICAL SCIENCE.

   1 On the Combined Action of a Current of Air, and the
   Pressure of the Atmosphere 193

   2 Considerations relative to Capillary Action 194

   3 Novel Use of the Plough 197

   4 Discovery of Rocks under the Surface of the Sea 198

   5 Paper to resist Humidity _ib._

   6 Professor Amici’s Microscopes _ib._

 II. CHEMICAL SCIENCE.

   1 On the Specific Heat of Gases 200

   2 On the Incandescence & Light of Lime 201

   3 Evolution of Heat during the Compression of Water _ib._

   4 On Electrical Excitation _ib._

   5 Magnetic Repulsion 202

   6 Diminished Solubility of Substances by Heat _ib._

   7 Composition of Cyanic Acid 203

   8 Iodous Acid 204

   9 Manganesic Acid _ib._

   10 Heavy Muriatic Ether, and Chloric Ether _ib._

   11 Test for the Presence of Nitric Acid 205

   12 Peculiar Formation of Nitre _ib._

   13 Experiments on Fluoric Acid and Fluates _ib._

   14 Crystallization of Phosphorus 206

   15 Solution of Phosphorus in Oils _ib._

   16 On the Inflammation of Powder, when struck by Brass 207

   17 Cementation of Iron by Cast Iron _ib._

   18 On the Preparation of Ferro-prussiate of Potash _ib._

   19 Sulphocyanide of Potassium in Saliva 208

   20 Decomposition of Sulphate of Copper, by Tartaric Acid
   _ib._

   21 Separation of Arsenic from Nickel, or Cobalt 209

   22 Chemical Researches into Certain Ancient Substances 209

   23 Compounds of Gold 210

   24 On the Bitter Substance produced by the Actions of Nitric
   Acid on Indigo, Silk, and Aloes _ib._

   25 On the Existence of Crystals of Oxalate of Lime in Plants
   214

   26 Fallacy of Infusion of Litmus as a Test _ib._

   27 Tests for the Natural Colouring Matter of Wine 215

   28 Test of the Presence of Opium _ib._

   29 Denarcotized Laudanum _ib._

   30 Extraction of Morphia from Dry Poppy Heads 216

   31 Preparation of Morphia _ib._

   32 Easy Method of Obtaining Meconic Acid 217

   33 On a New Vegetable Acid _ib._

   34 Altheine, a New Vegetable Principle _ib._

   35 Rheine, a New Substance from Rhubarb 218

   36 On Dragon’s Blood, and a New Substance which it contains
   _ib._

   37 Purification of Madder 219

   38 On Indigo, and Indigogene 220

   39 On the Mutual Action of Ethers, and other Substances 221

   40 Faraday’s _Chemical Manipulation_ _ib._

 III. NATURAL HISTORY.

   1 On the Supposed Influence of the Moon 222

   2 Luminous Appearances in the Atmosphere _ib._

   3 On the Determination of the Mean Temperature of the Air 223

   4 Indelible Writing _ib._

   5 Peculiar Crystals of Quartz _ib._

   6 Native Iron not Meteoric 224

   7 Native Argentiferous Gold 225

   8 Prothéeïte, a New Mineral 226

   9 Volcanic Bisulphuret of Copper _ib._

   10 Fall of the Lake Souwando, in Russia 227

   11 Vegetable Torpor in the Root of the Black Mulberry Tree
   228

   12 Method of increasing the Odour of Roses _ib._

   13 Pine Apples _ib._

   14 Mode of Condensing Vegetable Substances for Ship’s
   Provisions 229

   15 Rewards for the Discovery of Quinia, and for Lithotrity
   _ib._

   16 Upon the Gaseous Exhalations of the Skin 230

   17 Effects of Galvanism in Cases of Asphyxia by submersion
   _ib._

   18 Recovery from Drowning 231

   19 Preservation of Cantharides _ib._

   20 Chloride of Lime in cases of Burns _ib._

   21 Cure of Nasal Polypi 232

   22 Bite of the Viper _ib._

   23 Experiments on the Poison of the Viper _ib._

   24 Destruction of Moles _ib._

   25 On growing Salad Herbs at Sea 233

   26 Chinese Method of Fattening Fish 234

 Meteorological Diary for the Months of June, July,
 and August, 1827 236




 CONTENTS.
 _Oct.–Dec._ 1827.

 On the Means generally used with the Intention of curing a
 Stoop. By the late Mr. SHAW 237

 A Critique on the Aplanatic Object-glasses, for diverging
 Rays, of Vincent Chevalier, ainé et fils. By C. R.
 GORING, M.D. 248

 On the Existence of Chlorine in the Native Black Oxide of
 Manganese. By JOHN M’MULLEN, Esq. 258

 Modern Improvements of Horticulture 261

 FARADAY’s _Chemical Manipulation_, reviewed 275

 Statistical Notices suggested by the actual State of the
 British Empire, as exhibited in the last Population Census.
 Communicated by Mr. MERRITT 283

 On the Modern Ornaments of Architecture, &c. 292

 _De l’Influence des Agens Physiques sur la Vie_. Par W. F.
 EDWARDS, D.M. &c., reviewed 296

 Experiments on Thought 308

 Hieroglyphical Fragments, illustrative of Inscriptions
 preserved in the British Museum, with some remarks on Mr.
 Champollion’s opinions. In a letter to the Cav. San Quintino
 310

 On the Naturalization of Fish. By J. MAC CULLOCH,
 M.D., F.R.S., &c. 320

 WADD’s _Nugæ Chirurgicæ or, a Biographical
 Miscellany_, reviewed 329

 _Nugæ Canore, by_ UNUS QUORUM, reviewed _ib._

 WADD’s _Mems., Maxims, and Memoirs_, reviewed _ib._

 On Tic Douloureux 346

 Remarks on some Quadrupeds supposed by Naturalists to be
 extinct. By JOHN RANKING, Esq. 350

 Description of a cheap and portable Instrument for enabling
 Young People to acquire a knowledge of the Stars, or determine
 their situation in the Heavens. By S. LEE, Esq. 371

 CARUS’s _Introduction to the Comparative Anatomy of
 Animals_, reviewed 377

 _Comparative Value of the principal Varieties of Fuel, &c.,
 by_ MARCUS BULL, reviewed _ib._

 DANIELL’s _Meteorological Essays and Observations_,
 reviewed _ib._

 _Philosophical Transactions of the Royal Society for 1827_,
 reviewed _ib._

 _Practical Treatise on the use of the Blowpipe, by_ J.
 GRIFFIN, reviewed _ib._

 _Circle of the Seasons, and Practical Key to the Calendar and
 Almanack_, reviewed _ib._

 _Conversations on the Animal Economy_—reviewed _ib._

 Notice of a New Genus of Plants discovered in the Rocky
 Mountains of North America by Mr. DAVID DOUGLAS. By
 JOHN LINDLEY, Esq. 383

 A Description of the Aurora Borealis seen in London on the
 Evening and Night of the 25th of September, 1827, with
 Critical Remarks, &c. By E. A. KENDALL, Esq., F.S.A.
 385

 Proceedings of the Royal Society 424

 Proceedings of the Horticultural Society 425

 ASTRONOMICAL AND NAUTICAL COLLECTIONS

   i. Ephemeris of the periodical Comet for its Return in 1828,
   computed with the consideration of a resisting Medium. By
   Professor ENCKE 428

   ii. Elementary View of the undulatory Theory of Light. By
   Mr. FRESNELL 431

   iii. Remarks on the action of Corpuscular Forces. In a
   letter to Mr. POISSON 448

   iv. Calculations of Lunar Phenomena. By THOMAS
   HENDERSON, Esq. 450

 MISCELLANEOUS INTELLIGENCE.

 I. MECHANICAL SCIENCE.

   1 On the Adhesion of Screws 453

   2 Improvement in Steam-engines _ib._

   3 Improved Clock 454

   4 Method of dividing Glass by Friction _ib._

   5 Use of Soapstone in diminishing Friction 455

   6 On peculiar Physical Repulsions _ib._

   7 On the Magnetic Effects of Metals in Motion 456

   8 Duration of the Effects of Light upon the Eye 457

   9 On the Measurement of the Intensity of Light _ib._

   10 On the apparent Decomposition of White Light by a
   Reflecting Body when in Motion 458

   11 On the Barometer _ib._

   12 Easy method of reducing Barometrical Observations to a
   Standard Temperature _ib._

   13 Diamond Lenses 459

   14 Sapphire Lenses for Single Microscopes _ib._

   15 On a Method of securing and Preserving the Rowing Pins in
   Boats 460

   16 Cold Injection for Anatomical Preparation 461

 II. CHEMICAL SCIENCE.

   1 Extraordinary Experiments on Heat and Steam 461

   2 On the Use of feeble Electric Currents, for effecting the
   Combination of numerous Bodies 462

   3 Crystallization of Metallic Oxides 465

   4 On Bromine _ib._

   5 Elementary Nature of Bromine _ib._

   6 Quantity of Bromine in Sea-Water 466

   7 Sale of Bromine _ib._

   8 Preparation of Iodous Acid _ib._

   9 On a peculiar Nitric Acid, and Sulphate of Potash 467

   10 On certain Properties of Sulphur 468

   11 On the Fluidity of Sulphur and Phosphorus at common
   temperatures 469

   12 Separation of Selenium from Sulphur 470

   13 On a new Compound of Selenium and Oxygen—Selenic Acid 471

   14 Preparation of Hyposulphuric Acid 473

   15 Singular Habitude of Phosphoric Acid with Albumen 473

   16 Economical Preparation of Deutoxide of Barium 474

   17 Preparation of Aluminum—Chloride of Aluminum _ib._

   18 Mutual Action of Lime and Litharge 475

   19 New Chloride of Manganese discovered _ib._

   20 Preparation of pure Oxide of Zinc 476

   21 Deuto-Sulphuret of Cobalt _ib._

   22 Separation of Bismuth from Mercury by Potassium _ib._

   23 Sulphuret of Arsenic proportionate in Composition to
   Arsenic Acid _ib._

   24 New Double Chromates 477

   25 Dobereiner’s finely divided Platina 477

   26 New Metals 478

   27 Analysis of Porcelain Pottery, &c. _ib._

   28 On the Composition of simple Alimentary Substances 480

   29 Preparation of Sulphate of Quinia and Kinic Acid, without
   the use of Alcohol 482

   30 Pure Narcotine prepared 483

   31 Uncertain Nature of Jalapia _ib._

   32 Preparation of pure Mellitic Acid

   33 On a New Acid existing in Iceland Moss 484

   34 Remarks on the Preparation of M. Gautier’s
   Ferro-prussiate of Potash, as described in this Journal for
   July, 1827 _ib._

 III. NATURAL HISTORY.

   1 Squalls of Wind on the African Shores 486

   2 Destruction of an Oak by Lightning 487

   3 Description of a Meteoric Fire-Ball seen at New Haven _ib._

   4 Remarkable Meteoric Phenomenon 488

   5 Aurora Borealis seen in the Day-time at Cannonmills 489

   6 Aurora Borealis in Siberia _ib._

   7 On the Presence of Ammonia in Argillaceous Minerals _ib._

   8 Composition of Apatite 490

   9 Burmese Petroleum Wells _ib._

   10 Direction of the Branches of Trees _ib._

   11 Effects of Light on Vegetation _ib._

   12 Organization and Reproduction of the Trufle 491

   13 Alteration of Corn in a subterraneous Repository 492

   14 Quick Method of putting Insects to Death 493

   15 Destruction of Snails by common Salt _ib._

   16 Remarkable Hairy Man _ib._

   17 Application of Remedies by Absorption from the Surface
   _ib._

   18 On the Strix Cunicularia, or Coquimbo Owl 494

   19 Naturalization of Fish 496

   20 Mode of keeping Apples _ib._

   21 On the Cultivation and Forcing of Sea Kale 497

 Meteorological Table 500




 TO OUR READERS AND CORRESPONDENTS.


The drawings, illustrating the construction of a Blow-pipe, are not
sufficiently accurate to enable us to publish them. Our Correspondent
will observe that we have noticed another part of his letter.

We regret that we are unable to offer our Correspondent, upon the
subject of _Gas Works_, any precise information. There can be no
doubt that an atmosphere tainted by coal gas is injurious to animal
and vegetable life, but much will depend upon the extent of the
contamination, and other causes, of which our limits prevent mention.
To say nothing of danger from fire and from explosion, it has always
been matter of surprise to us that gas-works are tolerated by the
government in close and confined situations—that the Thames is
suffered still to be polluted with their offal, and that they are
sometimes placed close by the road side, (as at Brentford,) to the
nuisance of every one who passes. These matters want looking into.

Q. will find an answer to his question, in the “Gazette of Health”
for last July.

F. R. S. must remain unanswered till after St. Andrew’s Day.

Dr. Heinecken’s paper is disposed of as he desired.

Mr. BRANDE and Mr. FARADAY will commence their Lectures and
Demonstrations in Theoretical and Practical Chemistry, in the
Laboratory of the Royal Institution, _on Tuesday, the 9th of
October_, at Nine in the Morning precisely. Further particulars,
and a Prospectus, may be obtained at the Royal Institution, 21,
Albemarle-street, or by application to the Lecturers.

_In the Press_—A COLLECTION OF CHEMICAL TABLES, for the use of
Students, in Illustration of the Theory of Definite Proportionals, in
which are shewn the Equivalent Numbers of the Elementary Substances,
with the Weights and Volumes in which they combine, together with the
Composition of their most important Compounds, and the Authorities
for their Analysis. By WILLIAM THOMAS BRANDE.




 THE
 QUARTERLY JOURNAL
 OF
 SCIENCE, LITERATURE, AND ART.
 JULY—OCT. 1827.

 _On the Beauties contained in the Oval, and in the Elliptic Curves,
 both simple and combined, generated from the same Figure or Disk_.
 By R. R. Reinagle, Esq., R.A.

 Being the subject of a Discourse delivered at the Royal Institution
 of Great Britain.


After an apposite discourse to introduce the subject, the first
course taken, was to demonstrate the advantages of understanding the
right use of geometrical terms in our descriptions of the varieties
of shape, both in nature and art.

Every thing deserving the title of beautiful, and every grand object,
assume an outline of definite character: these are to be found in the
different classes of geometrical figures; the former in undulating
lines of elliptic curves, and grandeur in angular dispositions of
figure. All motion assumes a curved direction[1]. The primary and
leading object of the discourse was to prove the fact of original
beauty: and that a curved line was beautiful in an abstract point
of view, free from all associations. For this purpose there were
designed many diagrams on large black painted boards. [p002]

The explanation commenced with six or more parallel lines at equal
distances, and equal length, in an horizontal position to the eye of
the audience, _Fig._ 1; and another set of the same number of lines
drawn perpendicular, _Fig._ 2: these were demonstrated to possess not
the slightest character or principle of beauty in them, either as
separate lines, or collectively, however many.

 [Illustration: _Fig._ 1.]

 [Illustration: _Fig._ 2.]

 [Illustration: _Fig._ 3.]

 [Illustration: _Fig._ 4.]

The next diagram consisted of six or more radiating lines from
a centre, _Fig._ 3, and a corresponding number in an horizontal
direction, but of unequal quantities; they diminished like a flight
of steps, _Fig._ 4. It was then shown that the first means of
combining the six or more lines, which had been first drawn, so as
to please the eye, without creating any geometrical figure, was the
radiating principle. Our eye not only can tolerate that union of
lines, but receive the impression as pleasing in character; while all
lines parallel to each other, being right [p003] lines, and viewed
as a flight of steps, or pile of planks, opposite the observer, are
disagreeable. Upon the former principle it is, that the rays of the
sun, and rays of light generally, are so attractive and beautiful.
It is from this circumstance that right lines drawn in an inclined
position to the plane of the picture, derive an interest from the
angles engendered through the imagination.

 [Illustration: _Fig._ 5.]

 [Illustration: _Fig._ 6.]

 [Illustration: _Fig._ 7.]

 [Illustration: _Fig._ 8.]

To follow up the principle by regular steps, and to open a clear
view of the laws of beauty in lines, there were traced some inclined
right lines (_Fig._ 5), with a regular set of right angles upon it,
like the stems of leaves on each side. This exhibited no sort of
beauty, nor any other advantage than mere combinations of formal
angles. The next diagram (_Fig._ 6) was an inclined line as before,
with similar angular projecting stems, to which were added elliptic
curves on the upper side of each branch, that produced the form of a
leaf. _Fig._ 7 was another inclined line, having oval curves upon it.
Both these were shown to possess principles approaching to beauty, by
progressive advances in combination and original structure. _Fig._ 8
was an inclined line with the oval curves upon it; to which a similar
addition of elliptic curves were adjoined to the stems, [p004] as in
_Fig._ 6. This addition made a new advance towards beauty. _Fig._
9 commenced a more perfect principle of beauty, having an elliptic
stem with oval branches rising from it, as in the others. If to this,
the principle of gradation had been given, the eye would prefer it;
I mean, by a scale of increase from the top to the bottom of the
projecting stems: and if there had been superadded the external
contour of a lengthened egg, like the form of a sage leaf, we should,
step by step, advance into the region of beautiful character of
exterior shape. _Fig._ 10 is a retrograde, showing how uncongenial
angular forms are to curved lines, when producing ornament; at
least how little our eye can bear the angular projections from the
elliptic or oval turned stem. _Fig._ 11 was a curve of exactly the
same disk, with the same oval stems, to which a small serpentine
addition was made, expressing a leaf. Of all the last seven diagrams,
this abounded with the greatest portion of beautiful lines, and is
indisputably the most agreeable and beautiful. Combinations are like
numericals; many of these forms, placed together with judgment and
discretion, will attract us from the larger proportion of beauty
that meets the eye at once, like a head of beautiful hair: one hair,
however gracefully bent, cannot impress us like an entire lock of
the hair; nor will this [p005] curl charm us as the whole will on
the human head. We owe to construction and combination all our
pleasurable feelings of beauty: no person is allured by a single
feature of any species of objects: but a thousand, or a million,
arouses our anxious notice. Thus, the last diagram of the elliptic
stem and the foliage upon it, exhibited, by the continuity of curved
lines, the greatest approach to beauty, of all the figures presented
to the notice of the audience.

 [Illustration: _Fig._ 9.]

 [Illustration: _Fig._ 10.]

 [Illustration: _Fig._ 11.]

 [Illustration: _Fig._ 12.]

These preliminary designs opened the way for richer combinations; but
the subject affording such an immense field of variety, I confined
myself to the narrowest limits, and to one oval disk of seven inches
transverse diameter, from which seven different designs were shown on
paper. The first had a variety of serpentine lines placed at random,
all produced by the disk of the oval just named, and the confluent
lines of two such, placed side by side, or end to end, _Fig._ 12;
which oval disk was put upon the lines to prove the construction.
These lines, without expressing or forming any sort of figure,
exhibit a set of elegant curves, of varied quantities of convex and
concave, with which our eye will be more pleased than any set of
right lines similarly distributed, as in _Fig._ 13, which follows.
[p006]

 [Illustration: _Fig._ 13.]

 [Illustration: _Fig._ 14.]

Two other diagrams were placed before the company, each a circle of
12 ovals, from the same disk, revolved upon an axis, resting upon one
end of the transverse diameter, (the length-ways of the oval,) which
figure in the skeleton was a duodecagon. _Fig._ 14 is one of the
diagrams; the ovals folding regularly over each other. By suppressing
the continuity of the oval disk, where the lines would traverse, a
very pleasing figure [p007] is created. It may be easily converted
into foliage, and can be amazingly varied in principle, by having
fewer ovals, and making them revolve upon an arm or continuation of
a line from the transverse diameter. _Fig._ 15 is the same diagram,
with all the oval lines described, which forms a figure of elegant
intricacy; each member, or curvilinear subdivision, assumes a most
agreeable shape: the whole, at the first sight, does not carry the
evidence of being generated from the same disk. These agreeable
figures may be varied to an extraordinary extent: the two that were
presented were mere examples of some of the numerous changes that any
given oval disk may create.

 [Illustration: _Fig._ 15.]

 [Illustration: _Fig._ 16.]

 [Illustration: _Fig._ 17.]

The objects next presented, were three vases of very dissimilar
appearance, all produced from the same diagram of the oval; each in
a separate drawing. The first was like a Greek vase with handles;
its character established by employing certain proportions of
quantities, in seven parts. The body has four parts, the foot or
pedestal one; the neck two. The handles were regulated in the
position and projection by lines drawn from the bottom of the vase,
through the ovals which compose the outline of the two sides; and
passing through the transverse diameter. These handles were made
from an oval that was the length of half the line of the transverse
diameter, _Fig._ 16. The skeleton of angles that [p008] govern the
shape of this vase, is a very pretty figure of itself. The form does
not proceed from any caprice of irregularity, but is consistent
with rational organization, and symmetrical proportions. The figure
of the plate sufficiently describes the mode of making the diagram
without entering into the detail. _Fig._ 17 represents a tazza with
handles: the same disk is apparent, by the dotted lines that made the
first vase. The ovals [p009] are placed right and left of a central
perpendicular line, dividing the cup in two parts; the transverse
diameters meet in one line parallel to the base of the tazza; a
dotted outline expresses the angular position of the handles: the
concave lip of the tazza is made by the same oval disk, whose
transverse diameter leads to the under line of the folding edge of
the cup. The leg of the tazza is produced by the same small disk
that served for the handles of the first vase. The body of the vase
and the leg form two equal parts; the whole upper extent ought to be
seven parts, so that it is seven and two[2]; the width of the base
of the leg measures two parts, and the altitude three, of the seven
parts. These proportions cannot produce any other than agreeable
appearances, apply them as we may.

 [Illustration: _Fig._ 18.]

The third vase, exhibited an Hebe cup, with a handle, which presented
a totally different appearance in form to the two previous ones. It
was proportioned by similar principles: the larger disk made the
body, inclined right and left upon the end of the oval. The neck and
the leg were both made from the smaller oval disk; the dotted lines
to the ovals of the leg sufficiently show the fact. The handle and
concave lip of the cup were made by an application of the same disk.
The altitude contained four parts. The body two parts, the leg one
part, and the neck one other part; the handle rises one-eighth above:
every portion of this figure is created by the two disks previously
named. The foliage rises from below and descends from above,
one-fourth of the whole height of the body [p010] to the commencement
of the concavity of the neck, where the beading runs round.

I remarked, that by adhering to regular proportional quantities of 1
and 2, 3 and 5, 2 and 5, 7 and 5, 7 and 2, &c., and using elliptic
disks or curves, very great beauties are derived.

 [Illustration: _Fig._ 19.]

 [Illustration: _Fig._ 20.]

A skeleton of the tazza in angles was drawn on a black painted board,
together with oval disks placed upon those lines, which clearly
demonstrated the whole system of the construction. The explanation
of these various diagrams necessarily involved a circumstantial
description of each created figure, which were thoroughly analysed.
Quantity and variety were particularly dwelt upon, as absolutely
necessary to the production of perfect beauty; equalities being
unfriendly to that symmetry which accords with nature. Some other
diagrams were drawn, to show the inelegant appearance of radiating
lines from the concave or convex half of an oval or an ellipse,
_Fig._ 19: but by drawing another convex half of an oval, and placing
those lines as tangents, greater beauty was formed by the alternate
changes and varieties of inclination of each tangent, _Fig._ 20. This
was capable of an immediate adaptation to elegant vegetation; [p011]
a few convex and concave elliptic curves added to each tangent,
produced an ear of barley, or an ear of rye, the elegant construction
of which, is rarely noticed in our remarks on nature, _Fig._ 21.

 [Illustration: _Fig._ 21.]

The discussion on these various designs being concluded, some
important compositions of three great and renowned painters were
produced, to corroborate what had been advanced in support of the
native beauty of the oval and ellipse. Raphael’s grand composition of
the dispute on the Sacrament is in three grand oval curves.

The Doctors of the Church on the ground plan are ranged in an oval
convex line; and the heavenly Choirs engage two concave oval shapes
of the same proportion, but of unequal quantities. This is also a
proof of a composition of parts, bearing two to one.

The facility of expressing such a composition, by being geometrical,
is extremely easy.

The second illustration was the Aurora, by Guido, of the Aldobrandini
palace. This was pointed out to depend upon an oval curve, and
continued curvilinear details: the striking beauty of this fine
composition is owing to its great and simple elliptic curve, which
includes the whole group; the attendant hours have the principle of
radiating to a centre of the oval: thus harmonizing and uniting forms
congenial both to principle and nature.

The third grand composition was by Rubens, the Coronation ceremony of
Mary de Medicis, one of the grand Luxemburg pictures.

This very fine composition is contained in an oval concave [p012]
curve, and the figures in several points radiate to a centre. Some
of the group pass the great leading line, but only to the degree
and with the licence that a genius can effect, which destroys the
too great, and the too palpable construction of the composition.
The allegorical figures of Fame and Genius hovering over the royal
personage, establish a centre to the oval, which prevents a void that
would have been weak in the composition.

Three designs were next produced from Etruscan vases, to carry
the evidence further, and to show the original source of the
demonstrations of beauty in Grecian art. One was a charioteer driving
a pair of magnificent horses of the highest spirit, _Fig._ 22. The
composition is elliptic, and serpentine within.

 [Illustration: _Fig._ 22.]

The youthful conductor of the steeds is in a crescent or boat-shaped
car, and his form is elegantly bent to meet the action and motion;
his mantle flows behind in curved and serpentine folds, expressing
the wind occasioned by the velocity of action. A more graceful or
beautiful group and composition cannot be imagined.

The next design was a female in an elegant and very gentle serpentine
action of the figure. Every portion of the outlines was elegant,
from the varied succession of convexity and concavity; not a single
angle could be traced throughout the whole [p013] of this beautiful
creature. She held in her left arm a very handsome oval vase; and in
the other a sort of scarf with ribands, all serpentine in form. By
her side is placed a young man selected from another Etruscan design.

 [Illustration: _Fig._ 23.]

The line of this figure was the outline of an ellipse; it is
perfection in every respect; and the grace was shown to depend upon
gentle curved lines of convex and concave, alternately blended, and
confluent. The motion of ships at sea is described in gentle elliptic
curves; the wings and plumage of birds assume the oval and elliptic
curves; all the fibres of their feathers have that form; some
flattened, others more rounded: the pine-apple and numberless fruits
have all an oval character of outline.

Many take the character of eggs, pointed at one end, and large and
blunt at the other extremity. The leaves of trees [p014] have the
oval shape more than any other; the bend of the branches, and the
whole external form of many trees is oval.

There is no form of created things which may not be found to
correspond in all its dependent shapes to ovals and ellipses of
various disks, even objects which at first sight seem to contradict
the possibility of meeting this system.

The lecture was closed by some extracts and quotations from Lomazzo,
Dryden, Hogarth, Du Fresnoy, and the Abbé du Bos; the tendency
of which was to show that lines had been mentioned, and had been
written upon without any explanation given that could lead to certain
conclusions. That all these authors attributed to supreme genius
alone, and something of the divinely inspired character in artists,
the power to produce those indescribable lines that affect the human
eye so strongly. These lines I described as belonging to the oval and
the ellipsis, and the confluent lines by conjunction and combination;
that these indescribable lines, which from Plato to Dryden had never
been detected or obtained a name; that puzzled all equally alike, are
those alone I attempted, and I believe proved in this lecture, to be
the elliptic combinations.

I stated that the great Greek artists confined themselves to certain
rules and principles of unerring consequences in the production
of beauty, grace, or grandeur in their figures; that all their
compositions depended upon the same species of rule and order. I
pointed out, that fashion is in all countries the destroyer of
taste, that it unfits the mind for fixed principles; that where it
dominates, _there_ taste will be always fluttering and never settle,
nor have a sure dominion. The Greeks, having no such vile tormentor
to divert them from a pure course in their progress, arrived at the
summit of perfection in every scientific pursuit, by following sure
principles as their guides, and by never abandoning a path traced by
nature, and matured by the most sublime philosophy.


 FOOTNOTES:

 [1] A great number of geometrical diagrams were exhibited, from a
 single line, to angles, squares, oblongs, circles, ovals, cones,
 cylinders, spiral lines, and various serpentine lines, &c.

 [2] The whole extent of the tazza, including the projection of the
 handles, should be seven parts; and the height of the vase two of
 such seven parts.

[p015]




 _On the Art of forming Diamonds into single Lenses for
 Microscopes_.—By Mr. A. Pritchard.

 [Communicated by Dr. GORING.]


Of the various improvements in Microscopes originated by Dr. Goring,
that which he conceives to be the most important is the construction
of single magnifiers from adamant. The details relative to this novel
class of instruments, I have been induced to lay before the public.
Single microscopes naturally aplanatic, or at least sufficiently so
for practical purposes, possess an incontestable superiority over
all others, and must be recognised by the scientific as verging
towards the ultimatum of improvement in magnifying glasses. The
advantages obtained by the most improved compound engiscopes over
single microscopes resolve themselves into _the attainment of vision
without aberration with considerable angles of aperture_; but against
this must be set the never-to-be-forgotten fact, that they only show
us a _picture of an object instead of nature itself_; now a Diamond
Lens shows us our real object without any sensible aberration like
that produced by glass lenses; and we are entitled, I think, to
expect new discoveries in miscrosopic science, even at this late
period, _from very deep single lenses of adamant_[3]. I shall not
fatigue my [p016] readers by describing the difficulties which were
encountered in the prosecution of the design of making diamond
lenses. Nature does not seem to permit us to produce any thing of
surpassing excellence without proportional effort, and I shall simply
say, that in its infancy the project of grinding and polishing the
refractory substance of Adamant was far more hopeless than that of
making achromatic glass lenses of 0.2 of an inch focus. I conceive it
just to state that Messrs. Rundell and Bridge, of Ludgate-hill, had,
at the time of the commencement of my labours, many Dutch diamond
cutters at work, and that the foreman, Mr. Levi, with all his men,
assured me, that it was impossible to work diamonds into spherical
curves; the same opinion was also expressed by several others who
were considered of standard authority in such matters.

Notwithstanding this discouragement, in the summer of the year 1824,
I was instigated by Dr. Goring (at his expense) to undertake the
task of working a diamond lens: (being then under the tuition of Mr.
C. Varley, who was however at that time absent.) For this purpose,
Dr. G. forwarded to me a brilliant diamond, which, contrary to the
expectation of many, was at length ground into a spherical [p017]
figure, and examined by Mr. Levi, who expressed great astonishment
at it, and added that he was not acquainted with any means by which
that figure could have been effected: unfortunately this stone was
irrecoverably lost. Mr. Varley having returned from the country,
becoming now thoroughly heated with the project, permitted me to
complete another diamond, which had been presented to me by Dr. G.:
this is a plano-convex of about the 1/20th of an inch focus: it was
not thought advisable to polish it more than sufficed to enable us
to see objects through it, because several flaws, before invisible,
made their appearance in the process of polishing. In spite of all
its imperfections, it plainly convinced us of the superiority which
a _perfect diamond lens_ would possess by its style of performance,
both as a single magnifier and as the object lens of a compound
microscope. After the completion of my articles with Mr. V., being
entirely under my own command, I devoted some time to the formation
of a perfect diamond lens, and have at length succeeded in completing
a double convex of equal radii of about 1/25th of an inch focus,
bearing an aperture of 1/30th of an inch with distinctness on opaque
objects, and its entire diameter on transparent ones; it was finished
at the conclusion of last year. The date of its final completion
has by many been considered a remarkable epoch in the history of
the microscope, being the first perfect one ever _made_ or thought
of in any part of the world[4]. I think it sufficient to say of
this adamantine lens that it gives vision with a trifling chromatic
aberration, but in other respects exceedingly like that of Dr. G.’s
Amician reflector, but without its darkness: for it is quite evident
that its light must be superior to that of any compound microscope
whatever, acting with the same power and the same angle of aperture.
The advantage of seeing an object _without aberration_ by [p018]
the interposition of but a single magnifier, instead of looking at
a picture of it (however perfect) with an eye-glass, must surely be
duly appreciated by every person endowed with ordinary reason. It
requires little knowledge of optics to be convinced that the simple
unadulterated view of an object must enable us to look farther into
its real texture, than we can see by any artificial arrangement
whatever; it is like seeing an action performed instead of a scenic
representation of it, or being informed of its occurrence by the most
indisputable and accurate testimony.

Previous to grinding a diamond into a spherical figure, it is
absolutely necessary that it should be ground flat, and parallel
on both sides (if not a Laske or plate diamond), so that we may be
enabled to see through it, and try it as opticians try a piece of
flint glass: without this preparatory step, it will be extremely
dangerous to commence the process of grinding, for many diamonds
give a double, or even a species of triple refraction, forming
two or three images of an object; this polarization of the light,
arising from the primitive form of the crystal, of course totally
unfits them for making lenses[5]. I need not observe, that it must
be chosen of the finest water, and free from all visible flaws when
examined by a deep magnifier. It was extremely fortunate for diamond
lenses that the first made was free from the defect of double vision,
otherwise diamonds _en masse_ might at once have been abandoned as
unfit for optical purposes. The cause why some stones give single
vision, and others several peculiar refractions, may also arise
from different degrees of density or hardness occurring in the same
stone. Diamond-cutters are in the habit of designating stones male
and female, sometimes a _he_ and _she_ (as they have it) are united
in the same gem,—their _he_ means merely a hard stone, and their
_she_ a soft one. When a diamond which will give several refractions
is ground into a spherical figure and partially polished, it is seen
by the microscope to exhibit a [p019] peculiar appearance of an
aggregation of minute shivery cristallized flaws, sometimes radiated
and sometimes in one direction, which can never be polished out:
I believe I could disstinguish with certainty a bad lens from a
good one by this phenomenon without looking through it[6]. Precious
stones, from their crystalized texture, are liable to the same
defects for optical purposes as diamonds.

Having ascertained the goodness of a stone it must next be prepared
for grinding; it will in many cases be advisable to make diamond
lenses plano-convex, both because this figure gives a very low
aberration, and because it saves the trouble of grinding one side
of the stone. It must never be forgotten, that it may be possible
to neutralize the naturally low spherical aberration of a diamond
lens by giving it an improper figure, or by the injudicious position
of its sides in relation to the radiant. When the lens is to be
plano-convex, cause the flat side to be polished as truly plane as
possible, without ribs or scratches; for this purpose the diamond
should be so set as to possess the capability of being turned round,
that the proper direction with respect to the laminæ may be obtained:
when the flat side is completed, let the other side be worked against
another diamond, so as to be brought into a spherical figure by the
abrasion of its surface. When this is accomplished, a concave tool of
cast iron must be formed of the required curve in a lathe, having a
small mandril of about 2/10ths of an inch in diameter, and a velocity
of about 60 revolutions per second! The diamond must now be fixed
by a strong hard cement (made of equal parts of the best shell lac
and pumice-stone powder, carefully melted together without burning)
to a short handle, and held by the fingers against the concave tool
while revolving. This tool must be paved by diamond powder, hammered
into it by an hardened steel convex punch: when the lens is uniformly
ground all over, very fine sifted diamond-dust carefully washed in
oil must be applied to another iron concave tool (I may here remark,
that of all the metals which I have used for this purpose soft cast
iron is decidedly to be preferred): this tool must [p020] be supplied
with the finest washed powder till the lens is completely polished.
During the process of grinding, the stone should be examined by a
magnifying lens, to ascertain whether the figure is truly spherical;
for it sometimes will occur that the edges are ground quicker than
the centre, and hence it will assume the form of a colloid, and thus
be rendered unfit for microscopic purposes.

The spherical aberration of a diamond lens is extremely small, and
when compared with that of a glass lens the difference is rendered
strikingly apparent. This diminution of error in the diamond arises
from the enormous refractive power possessed by this brilliant
substance, and the consequent increase of amplification, with _very
shallow curves_. The longitudinal aberration of a plano-convex
diamond lens is only 0.955; while that of a glass one of the same
figure is 1.166; both numbers being enumerated in terms of their
thickness, and their convex surfaces exposed to parallel rays. But
the indistinctness produced by lenses, arises chiefly from every
mathematical point on the surface of an object being spread out into
a small circle; these circles, intermixing with each other, occasion
a confused view of the object. Now this error must necessarily
be in the ratio of the areas of these small circles, which being
respectively as the squares of their diameters, the lateral error
produced by a diamond lens will be 0.912; while that of a glass lens
of like curvature is 2.775; but the magnifying power of the diamond
lens will be to that of the glass as 8 to 3, their curves being
similar; (or, in other words, the superficial amplification of an
object; with the perfect diamond lens before mentioned, is 22500
times, while a similar magnifier, made of glass, amplifies only 3136
times, reckoning 6 inches as the standard of distinct vision:) thus
the diamond will enable us to gain more power than it is possible to
procure by lenses of glass, for the focal distance of the smallest
glass lens which can be well made is about the 1/80th of an inch,
while that of a diamond, worked in the same tools, would be only the
1/200th of an inch.

If we wish to compare the aberrations of the two lenses when of equal
power, the curvature of the glass must be increased; and as it is
well known the lateral aberration increases inversely as the square
of the radius, (the aperture and position remaining [p021] the same,)
the aberration of the diamond lens will only be about 1/20th of that
produced by the glass one, even when their thickness is the same; but
as the curvature of the diamond is less, the thickness may be greatly
diminished.

The chromatic dispersion of the adamant being nearly as low as that
of water, its effects in small lenses can barely be appreciated by
the eye, even in the examination of that valuable class of test
objects, which require enormous angles of aperture to be rendered
visible, which it is evident must be of easier attainment by diamond
magnifiers than by any other sort of microscope.

A mathematical investigation of the spherical aberration of the
diamond when formed into lenses, I hope to lay before the public at
a future opportunity. The comparative numbers here taken from the
longitudinal aberration are, I believe, sufficiently accurate for
practical purposes.

 _18, Picket-Street, Strand_.


 FOOTNOTES:

 [3] It seems generally admitted that, within a certain range of
 power not exceeding that of a lens of 1/20th of an inch focus,
 the beauty and truth of the vision given by the new compound
 microscopes cannot be equalled by that of any single instrument,
 at least of glass. It is no less true, however, that the _picture_
 of the compounds, however perfect, is not like a real object, will
 not admit of amplification beyond a certain point with advantage.
 Under the action of very deep eye-glasses, the image of opaque
 objects especially, first loses its strong, well-determined
 outline—then grows soft and nebulous, and finally melts away in
 shadowy confusion. Let the experiment be made of raising the power
 of a compound up to that of a 1/60th inch lens—then try it against
 the single microscope of that power (having, of course, the utmost
 opening the nature of the object viewed will permit). The observer,
 if open to conviction, will soon be taught the superior efficacy
 of the latter—for it will show the lines on the dust of Menelaus
 with such force and vivacity, that they will always be apparent
 _without any particular management of the light—nor can their image
 be extinguished by causing the illumination to be directed truly
 through the axis of the lens (as it always may in the compounds)_.
 A due consideration of the teeth and inequalities on the surface
 of a human hair, together with the _transverse connecting fibres
 between the lines on the scales of the curculio imperialis_, viewed
 as opaque objects, will suffice to complete the illustration of
 the subject; though the last object is not to be well seen by that
 kind of light which is given by silver cups—and a single lens of
 1/60th inch focus can of course have no other. The effectiveness and
 penetrating faculties of simple magnifiers are invariably increased
 by an accession of power however great—that of compounds seems to
 be deteriorated beyond certain limits. An opinion may be hazarded
 that the achromatics and reflectors yet made _do not really surpass
 the efficacy of equivalent single lenses, even of glass, when
 their power exceeds that of a_ 1/20th lens, from 1/20th to 1/40th
 the vision may be about equal—but from 1/40th upwards infinitely
 inferior.

 The superior light of the single refraction can need no comment—and
 it is evident that there must be a degree of power at which that
 of the compounds will become too dim and feeble for vision,—while
 that of the single instrument will still retain a due intensity.
 For these reasons it is conceived that the close and penetrating
 scrutiny of lenses of diamond of perhaps only the 1/200th inch
 focus, and an equal aperture (which their very low aberration would
 easily admit of,) must enable us to see further into the arcana of
 nature than we have yet been empowered to do. Glass globules of
 1/200th inch focus and indeed much deeper have been executed; but
 the testimony of _lenses_ of diamond would certainly be far more
 respectable, and is at least worthy of trial and examination.—C.R.G.

 [4] In Dr. Brewster’s treatise on new Philosophical instruments,
 Book 5, chap. 2, Page 403—Account of a new compound Microscope for
 objects of Natural History—is the following passage: “We cannot
 therefore expect any essential improvement in the single microscope,
 unless from the discovery of some transparent substance, which like
 the diamond combines a high refractive with a low dispersive power.”
 From which it seems certain that the Doctor never contemplated the
 possibility of working upon the substance of the diamond, though he
 must have been aware of its valuable properties.

 [5] There are fourteen different crystalline forms of the diamond,
 and of this number, from the laws which govern the polarization of
 light, the octohedron and truncated cube are probably the only ones
 that will give single vision. It is unfortunately very difficult
 to procure rough diamonds in this country, so we are compelled to
 use stones already cut, and to subject them to trial in the way
 mentioned in the text.

 [6] As many amateurs of science might take an interest in the
 inspection of the peculiar effect these lenses have on transmitted
 _light_, I shall be happy to exhibit them, as also the perfect lens.




 _Analysis of a newly-discovered Spring, at Stanley, near
 Wakefield_.—By Mr. William West.


Mineral springs, dependent for their characteristic properties on
carbonate of soda, appear to have been little noticed by chemists,
and to have been still less attended to as curative means; at least
in proportion to the multitude of cases in which that substance is
administered in various other forms. Indeed the inference to be
drawn from the silence respecting the modes of analysis adapted to
such waters in our best elementary treatises, is that they have
hitherto been very seldom met with. In one district, however, of
Yorkshire, carbonate of soda is of frequent occurrence; it is found
in the ordinary springs; often, at the same time with substances
with which, in artificial solutions, or when concentrated, it, would
be considered wholly incompatible; while at other times it is the
predominant, or the only remarkable saline constituent. An analysis
of a water of this kind, known by the name of the Holbeck Spa, has
lately been published in the Annals of Philosophy, by my friend E.
S. George; similar springs are found, I understand, as far [p022]
westward as Bradford; they are numerous from the borings in and near
Holbeck; while eight miles south, a water similar in its character,
but differing in containing about twice as much alkali in the same
measure, has been discovered at Stanley.

About two miles from Wakefield, near the Aberford or York road, is
an ancient mansion called Hatfield Hall; near the park or inclosure
of which, in boring for coal, the spring in question suddenly gushed
up, when the workmen had got to the depth of eighty yards, and has
continued to run spontaneously, in all seasons, at the rate of six
gallons per minute.

The water at the spring is limpid and very sparkling; the portion
which is allowed to escape, deposits upon the trough and in the
channel through which it runs a quantity of sulphur; the smell is
that of sulphuretted hydrogen; the taste, from the stimulus of the
bubbles of gas modifying the softness of the alkali, rather pleasant
than otherwise.

The appearances presented by re-agents are,—

With tincture of soap, a slight opalescence.

Nitrate of silver, an abundant precipitate, partially re-dissolved by
pure nitric acid.

Sulphate of silver, a precipitate only partially soluble in nitric or
acetic acid.

Muriate of barytes, a slight precipitate.

Lime-water, a precipitate soluble with effervescence in acetic acid.

Oxalate of ammonia, no precipitate.

On boiling, a slight pellicle appeared, soluble in nitric acid.

Carbonate of ammonia, no precipitate, nor any on the subsequent
addition of phosphate of soda.

The water restored the colour of litmus paper slightly reddened.

With tincture of galls and ferrocyanate of potash, no change.

With muriate of lime, the water remained unchanged until heated; but
when boiled, a copious precipitate took place.

When concentrated by boiling, the water reddened turmeric paper, and
effervesced strongly on the addition of an acid.

Nitromuriate of platina produced no precipitate, however concentrated
the water might be. [p023]

The results of the previous experiments indicate the presence of

 Soda,               Lime in small proportion,
 Muriatic acid,      No magnesia,
 Sulphuric acid,     No iron,
 Carbonic acid,      No potash.

A. To ascertain the proportion of sulphuric acid, sixteen ounces
by measure, previously saturated by acetic acid, were treated with
muriate of barytes; the precipitate, washed and dried, weighed
one grain; this indicates, in the imperial gallon, 3.2 grains of
sulphuric acid, equivalent to 5.8 sulphate of soda, dry, or 13 grains
crystallized.

B. For the muriatic acid; nitrate of silver, added to sixteen ounces
of the water boiled, and the alkali previously saturated, gave a
precipitate weighing 2.8 grains; reduced to the proportion in the
imperial gallon, this amounts to 26.9 grains chloride of silver,
equivalent to 11 grains chloride of sodium (muriate of soda.)

C. The crystalline pellicle separated from a pint of sixteen ounces,
on boiling, weighed 0.2 grains.

This was carbonate of lime; but in the water the lime would be
combined with muriatic acid, forming 0.22; or, in the imperial
gallon, 2.1 dry chloride, or 3.75 crystallized muriate of lime.

D. The precipitate formed on boiling with muriate of lime, weighed
from the pint, 3.6 grains; from the imperial gallon, 34.6 grains;
showing the water to contain in that quantity a carbonated alkali
equivalent to 53 grains of dry, or 59.5 crystallized bi-carbonate of
soda.

E. Muriate of barytes, added to the water left on evaporating sixteen
ounces to two, gave a precipitate weighing 8.2 grains; deducting one
grain for sulphate of barytes, as found in experiment A, we have 7.2
carbonate of barytes; this indicates in the gallon 53 grains of dry,
and 59.5 of crystallized carbonate of soda, as in the last experiment.

Lastly, a pint of sixteen ounces of the water, evaporated to dryness,
furnished in three trials of saline residuum, weighed after short
exposure to a dull red heat, six grains, or 57.6 from [p024] the
imperial gallon. Now we have seen that this would consist of

  5.8      Dry sulphate of soda   (exp. A).
 11.           Chloride of sodium ( —  B).
  1.9          Carbonate of lime  ( —  C).
 ----
 18.7
 38.9
 ----
 57.6

The remainder, 38.9, having been converted by the heat into
proto-carbonate of soda, is equivalent to 54.5 dry, 61 grains
crystallized bi-carbonate, agreeing nearly with the quantities found
from experiments D and E.

Following, as I do, that doctrine which supposes the bases to be
distributed among the acids in a mineral water in the combinations
which possess the greatest solubility, we must suppose the lime to be
in the state of muriate; we shall then have to diminish the muriate,
and increase the carbonate of soda: so that on this view, the saline
constituents of an imperial gallon, in the state in which they exist
in the water, are,—

Soda in combination with carbonic acid, equivalent to

 Bi-carbonate or super-carbonate  56 gr. dry.  62.5 crystallized
 of soda

 Sulphate of soda                  5.8  ditto  13     ditto

 Muriate of soda (chloride         8.75 ditto   8.75  ditto
 of sodium)

 Muriate of lime                   2.1  ditto   3.75  ditto

The gaseous contents of the water consist of variable proportions
of carbonic acid, sulphuretted hydrogen, and carburetted hydrogen;
the latter gas is continually emitted from the spring, in greater
quantity than the water can absorb; and a portion of the other two
also escapes from its surface. I have made many experiments on
the gas, separated by boiling; but find the results, as I might
anticipate, altogether inconclusive and uncertain. In waters
containing, as at Harrogate, these gases with muriates or sulphates,
boiling may be expected almost wholly to disengage them; but in this
case the affinity of the soda in dilute solution, is likely to retain
the carbonic [p025] acid, and even to cause a decomposition of the
sulphuretted hydrogen, so as to prevent our obtaining, in a gaseous
form, the quantity really existing in the water, and imparting to it
sensible or medicinal properties.

On the subject of medicinal qualities I am at all times cautious of
giving an opinion: but I may observe, first, that as this spring is
dissimilar to any of those which have already attained celebrity, so
none of them can form a substitute for this; it is not Harrogate,
or Cheltenham, or Buxton, or Tunbridge water: the alkaline springs
of the West Riding, of which this is by far the strongest, stand
as medicinal waters hitherto alone; the active ingredient, the
bi-carbonate of soda, being spoken of in chemical works, as “rarely
found in mineral waters.”

Secondly, from the known properties of this substance, carbonate
of soda, and the frequency of its administration in a long train
of arthritic, calculous and dyspeptic complaints, the water must
be highly useful as an anti-acid and as a diuretic; and as the
advantages which native mineral waters possess over artificial
solutions of the substances, in the great degree of dilution, and
the impregnation with gases, and still more in the adjuncts of
leisure, exercise, pure air, regulated diet and early rising, are of
especial consequence in the latter very numerous class of diseases,
those called stomach and nervous complaints; we may fairly suppose
that such a spring will be found to be a valuable addition to those
previously known, applying, as it does, to cases of such frequent
occurrence.




 _Observations on the State of Naval Construction in this Country_.


It appears that there is at present a tendency to improvement in
every branch of science; monopoly in intellect may now be said
to be vanishing; and empiricism is obliged to seek dark corners,
to escape the light which is penetrating into regions from which
it had but very lately been excluded. The administration, too,
encourages advance of knowledge; yet notwithstanding these favourable
circumstances, there still exists, in [p026] some minds, an
inaptitude of scientific perception, which induces unwillingness to
acknowledge the advantage that results from the application of the
exact sciences to the useful arts.

This neglect of scientific principles is nowhere more manifest than
in the affairs of naval architecture, and it is not confined to the
Royal Navy, but extends also to our mercantile shipping; and hence
it is that our commercial marine is in some respects behind foreign
nations, especially the Americans, in the formation of its ships:
our merchantmen are, almost without exception, the most unsafe[7]
and slowest ships in the world. The ship-owners, therefore, would do
well to consider this circumstance, and endeavour to devise means of
introducing science into the merchant yards. The establishment of the
new university in the metropolis affords an opportunity of doing it
at a comparatively small expense, by the foundation of Lectures on
the theory of Naval Architecture; and the support even of a separate
institution in the vicinity of the merchant yards of this great port,
for the education of ship surveyors, would soon be repaid by the
improved character of our merchant shipping.

If the science of Naval Architecture depend on certain
physico-mathematical laws, as no doubt it does, it is monstrous to
imagine for a moment that such laws can be developed by a flight of
fancy, or that a man is born with an _intuitive optical_ perception
of the lines of least resistance, &c., or, in the jargon of the
craniologists, that he has a naval-architectural bump on his skull;
yet one would think that such was the case, when we see men, we
cannot say philosophers, start up and loudly assert that they are
in possession of the secret of construction; and they are believed
because their hypotheses are never submitted to the examination of
those who are capable of detecting their fallacy.

The Experimental Squadrons have, with a multitude of perplexing
results, elicited, it must be confessed, at least an interesting
fact, viz. that there has been an establishment seventeen years in
this country, in Portsmouth dockyard, for the scientific education
of naval architects, for the Royal [p027] Navy.[8] From the plan of
education, as laid down by the Commissioners of Naval Revision in
1810, it appears that, to a requisite knowledge of the _practice_
of their profession, the gentlemen composing this body of naval
constructors unite a sound and competent one of its _theory_[9].

It can only be from such a source that we can look for the
improvement of our men of war, and it is to be regretted that every
means should not be taken to avail ourselves of it: but unhappily
such is the force of prejudice that, unless some alteration should be
adopted in this institution, it will be in vain to expect advantage
from it.

The objection urged against this establishment, namely, that the
scientific education it gives to its members precludes them from the
attainment of a due knowledge of the practical construction of our
ships, is so absurd, that none but weak or jealous minds could ever
have brought it forward. Shall it be laid down, in the present age,
as an axiom, that a profound ignorance of the principles of his art
is the one thing essential to the formation of what is generally
meant by the term “practical man?” We contend that, having made,
_in vain_,[10] a long and most indulgent trial of a system without
science, if we may use such an expression, we must extend to one
in alliance with it, a like patronage, before we can be allowed to
pronounce a fair and legitimate judgment upon its efficiency.

But even in the peculiar path in which the naval architects educated
at Portsmouth might be supposed to excel, we do not find that any
opportunity is allowed them to come forward, nor shall we see this
until some effort is made by the heads of our naval departments, to
allow a broad and open competition to take place. It may be urged,
that the learned Professor at Portsmouth (Dr. Inman) in himself
includes all that can have [p028] possibly been taught or understood
in the establishment over which he presides, and that therefore he
is the representative of it in the late and present trials for the
palm of excellence; but we cannot by any means assent to this: many
of the students must have left his tuition seven, eight, and nine
years, and must be between thirty and forty years of age; and it
would be strange indeed, if during such a period, and in the prime
of life and intellect, some of these, if not all, had not cultivated
the science after their own bent of mind, and formed original ideas
on the subject: we say, therefore, that Dr. Inman’s constructions
cannot be called the production of the establishment—they are merely
the effort of one man, whose attention it appears is distracted by a
multiplicity of occupations, and can only, along with the vessels of
Capts. Symonds, Hayes, and Sir R. Seppings, be deemed criterions of
the particular views of an individual.

Mysticism and ignorance always accompany each other; and we may
reckon that in proportion as the latter disappears from amongst our
ship-builders, so will the absurd vagaries of the former recede, and
the subject be placed at last on the true principles of philosophical
induction, instead of the caprices of imagination. We look forward,
therefore, to this new body of naval architects for the expulsion of
all quackery from their profession, and for the exposition not only
of what we really do know, but also of what we do not know about it:
this is the only way to arrive at truth, which should be the sole
object of all investigation; but which we are afraid has hitherto
been sadly garbled and perverted wherever it has had to do with naval
architecture in this country.

But we repeat that we do not see that the nation is at all likely to
benefit from the science or exertions of those gentlemen so long as
they are placed in situations where a superior education can have no
other effect than producing disgust and chagrin in the mind of the
possessor; and if the institution at Portsmouth be designed for no
better purpose than that of supplying house-carpenters, joiners, and
still more inferior trades, with foremen, it had better be abolished.
Some would regard it, as at present used, as a gross mockery on the
public [p029] at whose expense it is supported; it is certainly a
cruel one of those who have been induced, by the fair and brilliant
prospects held out to them of support and encouragement, to devote
their lives to this branch of the public service.

But to return to the Experimental Squadron: it is with regret that
we must conclude, upon a careful consideration, that, although the
experiments are carried on with so much vigour and interest, they are
evidently founded on imaginative views, and that there cannot exist
any thing like legitimate data where so many failures and anomalous
results obtain. Who can read the account of the first Experimental
Squadron[11], without immediately perceiving that the constructors
of the contending vessels, however sanguine each might have been of
the success of his particular fancy, met with nothing but the most
perplexing results? We see sometimes one and sometimes the other
vessel claim the palm of excellence, and finally leaving the subject
as much in the dark as ever. This is the natural consequence of the
non-application of inductive philosophy to the question before us,
and the most important conclusion that can be gathered from the
experiment is, that we have begun at the wrong end, and that it is
high time to employ analysis instead of synthesis to effect the
desired objects: for in the present state of the theory of naval
construction in this country, there are yet no data existing to
effect with precision and confidence the synthetical composition of a
ship.

We cannot refrain here from noticing the paucity of information
contained in the reports hitherto made on the first Experimental
Squadron. The best one[11] is but little removed from a ship’s
log book, and in some respects is inferior to it: it is of such
a scanty nature, that we can scarcely inform ourselves on any
point, and that only in a _relative_ degree, of the qualities of
the vessels composing it: we cannot find out any mention of their
_absolute_ velocities on the different points of sailing, which is
a most important omission. We are neither informed in what way the
observations were conducted, whether they were made simultaneously
or not: unless the former, any attempt at comparison must be very
doubtful, if not entirely fallacious. Circumstances of wind and
the weather may very widely alter in the [p030] course of a short
time, and every endeavour at legitimate analogy be destroyed by such
variation. We strongly suspect that this is one cause of perplexity;
and another prolific one is the vague idea given of the strength of
winds by nautical language. Nothing but the determinations of the
anemometer should ever be allowed to appear in an account of such
experiments. Every circumstance attendant on the quantity and trim of
sail, the heeling, the rolling and pitching of the ship, position of
the rudder, &c. should be accurately ascertained and _tabulated_; for
it is next to an impossibility and a wilful waste of time to attempt
to institute comparisons without pursuing a system of tabulated
results, which should be kept in the same form on board each ship.

We must also express our regret that the scientific professor at
Portsmouth does not appear to have ascertained the position of the
centre of gravity of any of his ships, with regard to height, by the
simple and easy experiment long known in principle, and described
lately with geometrical rigidity in two or three publications by
some of his pupils[12]. The knowledge of the position of this point
would have placed him so far above his competitors, in so many
important particulars, that we are surprised he should have thrown
away his advantage, and descended to a level with his less scientific
opponents. We are afraid that, here again, imaginative views have
stepped in, and taken the sober mathematician from the only path by
which excellence can be attained. We are at a loss to conceive how
the stabilities of his ships can be said to be ascertained without
the knowledge of the position of this point.

Some of the obscurity which pervades this difficult subject may be
overcome, as to broad and general principles, by attentively and
_coolly_ observing the progress of marine architecture, since the
introduction of cannon into naval warfare, and more particularly
during the last century and a half. We shall then clearly perceive
that the French, who, as early as the beginning of the reign of Louis
XIV., employed men of first-rate talent in their naval arsenals,
and neglected no opportunity for the [p031] advancement of science
in them, increased and kept increasing the dimensions of their
ships, more especially the length, the ratio of which to the breadth
has been augmented by them from about 3-1/4.1, to 4.1 within the
last century. While this principle was acted on, the improvement
of their ships was gradual; and by referring to our own progress
in the art, in tardy imitation of the practice of the French, we
shall likewise conclude that our navy has derived precisely similar
advantages from the same causes. Here we have at once two grand but
_concurring_ results derived from an experiment, not made on one or
half a dozen different vessels, but on the whole navies of the two
most powerful maritime states in the world: and if to these we choose
to add the result of the practice of the same means on the Spanish
and other navies, we might surely be warranted in saying, from this
broad but _certain analysis_ of _facts_, that, in relation to the
hull, the _general increase of dimensions, with a greater relative
length_, is one cause of the improvements that have been made in the
sea-going qualities of the ships composing the fleets of the present
maritime powers: the question therefore that remains to be decided
on in relation to this principle is, whether we have arrived at its
utmost practicable limits, or rather, whether we have arrived at the
_maximum_ of improvement it is capable of producing.

This brings us again to the experimental squadrons, as far as they
are connected with, and illustrative of, our observations; and the
first question naturally put forward about them is, whether there be
any thing very peculiar in the formation or dimensions of the rival
vessels? We suspect that the answer cannot otherwise than disclose,
that neither in principle, dimensions, nor in the formation, can they
be said to differ very materially from each other, or from ships of
the common construction: indeed we perceive in some a retrogression
of ideas and a violation of the principle, that the increase of the
ratio of the length to the breadth, in conjunction with a general
increase of dimensions, has been a predominant cause of improvement.
The fact also of so immaterial a difference necessarily includes a
system of masting and sails equally confined, and totally inadequate
to produce any great superiority of sailing over ships to which they
are so nearly equal in principal dimensions. [p032]

After so many years of trial with the present nearly invariable set
of principal dimensions, during which period it may be said, that
every possible contour of hull has been experimented on with them,
we are inclined to think that almost all has been done that could
be done under such restrictions, and that some great step must be
made in one or other of the principal dimensions themselves, with
correspondent alterations in the masting, before we can expect to
see a decided and great improvement in the sailing of our ships.
The depth is an element which has arrived at its limit from very
apparent external causes; but the length and breadth remain to the
skilful constructor without any such clogs to his endeavours; and
he has only to accommodate their relation to each other in the
manner most conducive to velocity, which in our opinion is the very
capital object of naval construction, both in ships of war and of
commerce. That it is so in the former, no one will, we apprehend, on
due reflection deny; but there will be many who will assert that it
cannot be obtained, in the latter, without a sacrifice of capacity;
which will defeat the object of carrying large cargoes: to this
we may reply, that if a vessel with an expense of one quarter the
capacity can make _three_ voyages instead of _two_, will not the
merchant be still a considerable gainer in capacity, and still more
so by a ready return of his capital[13]?

All observations on well-conducted experiments concur in proving that
velocity is gained by increasing the length, to a much greater degree
in relation to the breadth, than has ever yet been done in ships; and
that the increase of the same element contributes to their weathering
powers is too obvious to need insisting upon: it is also generally
advantageous, when not carried to an extent which would seriously
retard the manœuvring of the ship. This limit has not yet by any
means been determined; for it must be recollected, that although
the additional length increases the resistance to rotation about a
vertical axis, yet the power of the sails to give rotation about the
same is also increased, although not in so high a ratio. The power of
the rudder to produce rotation is also greater in a long ship than
in [p033] a short one, not only on account of the greater distance
it is from the axis of rotation, but also on account of the greater
velocity, and the more direct impulse of the water on it.

The increase of the ratio of the length to the breadth to produce
velocity should not interfere with the increase of breadth necessary
to produce stability or capacity; for both these qualities, varying
as higher powers of the breadth, a very small increase of breadth may
be attended with a considerable increase of length. If we compare
the Caledonia’s (120 guns) dimensions with those of the Royal George
and Queen Charlotte[14], of 1788 and 1789, we shall find, that 13
or 14 times as much length as breadth has been added to the first
rates of our navy. If we refer to the dimensions of the Commerce
de Marseilles, and those of the next preceding three-decker of the
French navy (for instance, the Ville de Paris[15], taken in Lord
Rodney’s action), we shall find that the French naval architects gave
in her 21 times as much increase to the length as to the breadth. If
this could be done with safety in a three-decked ship, with such a
vast top weight, much more could it be carried advantageously into
effect in ships of two decks, and frigates; but we do not find, in
the latter classes of the ships of the French navy, the increase of
length to go beyond six times that of the breadth. If we refer to the
Old Bellerophon, built in 1772, and the New Bellerophon, built in
1819, we shall find an increase of 24 feet in length, to 1.58 feet
increase of breadth; or the former more than 15 times the latter[16].

To those who oppose the objection that a greater length than at
present used would make the manœuvring of a ship too slow, we answer,
that as the Caledonia and the present first rates of our navy,
although from 10 to 15 feet longer than our two-deckers, are found to
be capital ships in this respect, there is a sure ground to believe,
that the addition of 20 feet in length to the present two-deckers
would not render their celerity [p034] of evolution less than that of
the three-decker; and since, from the reduction of weight aloft, the
centre of gravity would be lowered, and the displacement required to
be less, a somewhat smaller breadth might be allowed to a two-decked
ship of 206 feet long, than to one of 196 feet (especially since
the quantity of sail, remaining the same, is lowered by one whole
depth between deck), a smaller midship section would be, _cæteris
paribus_, required; the velocity of this ship might be considerably
increased. Nothing however can be precisely determined on, with such
a complication of circumstances, beyond a general idea. Calculation
and a strict analysis of ships must be resorted to, in order to fill
up the outline of our reasoning.

But for the same reason that we imagine that an addition of 20 or
perhaps 40 feet would not sensibly injure the celerity of manœuvring
of our two-deckers, we should think that the same increase of this
dimension might be tried without much risk to our first rates, with
an increase of breadth not exceeding 1/20th part that is given to the
length.

We repeat that the very capital object of the science of Naval
Construction is _velocity_, and we are decidedly of opinion that
it is attainable in a much higher degree than at present, without
compromising other necessary qualities, for which we have the
concurrence of facts as far as they go.

The Anglo-Americans, in the last war, took every possible advantage
suggested by views similar to those we have been adverting to, in
the construction of their large frigates. They had, it may be said,
to create a martial navy, and they had to oppose it against fearful
odds; but, free from the prejudices and errors so blindly cherished
by their opponents, and which constantly oppose reform by always
declaring the present practice to be the best, they did not retread
the old path, but began at its last step, and boldly advanced on
this principle into all the branches of the art. They built vessels
upon the most enlarged dimensions, and of a superior weight of
metal, and gave an increased ratio of length to the breadth. The
result of such a procedure, justified the confidence of the American
naval architects in only _one_ maxim, founded upon the _scientific_
observation of facts, and may give us a faint idea of what might
be effected by a still more enlarged and mathematical analysis.
[p035] Our frigates were so inferior to theirs in every way, that
they brought nothing but disasters upon us, excepting in the action
between the Shannon and Chesapeake, and one or two others, where,
assured by their previous successes, our gallant opponents threw away
the advantages possessed by their ships, by coming to close quarters
at once, and deciding the contest hand to hand.—Our ships of the line
could never bring these frigates to action, and owing alone to their
extraordinary sailing, did they evade and mock a large British fleet.
We were finally obliged to build 60-gun frigates after their method,
but when it was _too late_ for the exigency of the period; and thus
it has ever been our fate, for want of science in the constructors of
our navy, to follow the steps of our enemies at a humble distance,
and to be only then driven out of the old track by a terrible
experience of its inefficiency.

Nor have the Americans stopped here;—Mr. Huskisson plainly tells us
that “America is, year after year, augmenting its military marine, by
building ships of war of the largest class[17].” According to Capt.
Brenton, they have built a first-rate[18] of 245 feet length on the
gun deck, and 56 feet broad[19], to carry 42-pounders on the lower
deck, and 32-pounders on the other decks.

Our small class of 74-gun ships lately converted into frigates
carrying _fifty_ 32-pounder guns, we are fearful can only produce
disappointment if ever brought against the American frigates (not by
conversion, but by _construction_), which carry _sixty-two_ guns of
the same calibre, and are 180 feet long on the gun deck.

We must not forget also that our active neighbours the French have
now adopted a most formidable description of [p036] frigates, with
curvilinear sterns[20], and many other important improvements. They
mount 60 guns and carronades—viz. 24-pounders on the gun deck, and
36-pounder carronades on the flush deck.—The former calibre is
equivalent very nearly to 26, and the latter to 39 lbs. avoirdupois.

When we reflect on these circumstances, we cannot but feel surprised
that so many frigates of inferior force and dimensions should be
building in our dockyards. In time of emergency they will only bring
on us a repetition of former disasters and deficiency. We contend
that, instead of building ships of only _equal_ force to those of our
rivals, and thus _waiting_ for the developement of _their_ designs
before we can venture on a single step, we should build beyond them
in every respect. It must and ought to be recollected, that peace in
these matters produces a contest of intellect, and those will have
the advantage in it who attack instead of standing on the defensive.
We ought to lead the way, and to be at the head of the maritime
world, not in _number_ alone, but also in the _individual force and
qualities_ of our ships.

Having expatiated on the advantages of an increased ratio of length
to breadth in relation to the hull of a ship, we will just glance
at some of the principal effects it would have upon the masting
and sails; and here again we conceive that Professor Inman has, in
common with many others, relinquished the many good effects resulting
from it, for the inadequate one, of being able to carry a somewhat
greater quantity of sail, which must necessarily be lofty, and which,
(setting aside this detracting circumstance,) as the velocity of a
ship varies only as a _fractional_ power of the surface of canvas
spread, cannot produce the degree of fast sailing to be wished for,
but at an immense and impracticable quantity of sail[21].

A greater proof of the inadequacy of the present system of [p037]
lofty sail cannot be cited than the fact of its not procuring, under
the most favourable circumstances, a rate of sailing rarely exceeding
one-fourth the velocity of the wind.

As the number of masts should be so regulated as to create facility
in managing the canvas, which is well known to be at present hardly
manageable in a gale of wind, on board large ships, from the enormous
size of each individual course and topsail, we should not hesitate,
therefore, to have _four_ vertical masts, as recommended by Bouguer,
instead of three, in ships built in accordance with the principles
we have been discussing. This would, _cæteris paribus_, require
shorter masting and smaller yards, and the sails being much less,
individually, would be more easily managed and not so liable to
accidents.

From what has been said, and the actual experiments now pending, it
is apparent that the theoretic construction of ships is at a very
low ebb in this country; yet a fine opportunity now presents itself,
if we choose to avail ourselves of it, for rescuing the nation from
this generally acknowledged odium. Let a proper use be made of the
corps of Naval Architects we have, somehow or other, at last got, and
let their exertions, under a degree of encouragement equal to that
bestowed on the old ship-builders _in vain_ for so long a period, be
directed towards the improvement of their art. If they fail, they
cannot claim the excuse of having their endeavours repressed; if they
succeed, as no doubt they will, in advancing their profession to
something beyond mere carpentry, we shall be enabled to bid adieu to
the old and _ruinous_ method of blundering, under the reign of which
nothing but disappointment can ever be reasonably expected.

We have seen and do still see the immense advantages derived by our
country from the encouragement of those branches of science connected
with its manufactures and agriculture; and if we wish to keep our
present superiority, we must follow up vigorously this principle in
all its universality. To the cavils of ignorance and bigotry against
such a mode of proceeding we would answer, in the words of one of
the most enlightened members of the present administration, “This
country cannot stand still, whilst others are advancing in science,
in [p038] industry, in every thing which contributes to increase the
power of empires, and to multiply the means of comfort and enjoyment
to civilized man.”[22]

It is to be hoped, therefore, that His Royal Highness the Lord High
Admiral will extend to this most important national institution, the
School of Naval Architecture, the same vigilant and scrutinizing
eye that every other branch of our naval system is at this moment
experiencing from him, and that he will extend to it that fair play
and encouragement which has hitherto been denied to it. As a seaman,
he can fully appreciate and understand how much the bad qualities of
a ship may neutralize the best exertions of the most experienced and
skilful sailor; and, on the contrary, what a degree of confidence
may be insured in naval operations with excellent ships. We feel
persuaded, therefore, that he will not allow others to think for him
in a matter of so much national importance, and thus allow private
ends to interpose to the disadvantage of public views; but that he
will investigate and judge for himself. We would humbly suggest to
His Royal Highness to inquire into the individual acquirements and
productions, both of a _theoretical_ and _practical_ nature, of those
who have been educated in this establishment, and he would soon be
able to decide whether they be fitting or not for the important task
of constructing our ships, and for the confidence and protection
which we think we have shown has hitherto been ill-advisedly withheld
from them. Such a line of conduct would very soon carry our naval
architecture to a pitch of excellence _worthy_ of imitation, and
instead of being indebted to foreigners for models, we should be
able, with just pride, to point to the productions of British science
and intellect in this noble art.


 FOOTNOTES:

 [7] By referring to Lloyd’s List, it will appear, upon a moderate
 average, that _three_ English merchant vessels are lost every _two_
 days!

 [8] See No. II. of the Naval and Military Magazine, published in
 June last.

 [9] This will be readily acknowledged by those who will choose
 to read the “Papers on Naval Architecture,” and the “Essays and
 Gleanings on Naval Architecture,” two periodical works proceeding
 from the members of this institution.

 [10] See the Third Report of the Commissioners of Naval Revision,
 and the Resolutions of the Society for the Improvement of Naval
 Architecture, in which the old system of providing ship-builders for
 the Royal Navy is condemned in the most unqualified terms.

 [11] Vide No. 1 of the Papers on Naval Architecture.

 [12] Vide Annals of Philosophy, for November, 1826; No. 1 of the
 Papers on Naval Architecture, and No. 11 of the Essays and Gleanings
 on Naval Architecture.

 [13] Foreign nations, and more particularly the Americans, find
 their advantage in having swift merchant ships, and therefore our
 assertion is warranted by facts.

 [14] Caledonia, length 205 feet, breadth 53.5; Royal George, length
 187 feet, breadth 52.33 feet; Queen Charlotte, length 190 feet,
 breadth 52.33 feet.

 [15] Ville de Paris, length 185.62 feet; breadth 52.7 feet; Commerce
 de Marseilles, length 208.33 feet, breadth 54.79 feet.

 [16] Old Bellerophon, length 168 feet, breadth 47.33 feet; New
 Bellerophon, length 192 feet, breadth 49 feet.

 [17] Vide this gentleman’s speech on the Shipping Interests in the
 House of Commons, May 1827.

 [18] Called by Capt. Brenton the Ohio; but it appears from Lieut.
 De Roos’ personal narrative, just published, that the Ohio is a
 two-decker of 102 guns. It is to be supposed, therefore, that the
 three-decker of 135 guns, called the Pennsylvania by the latter, is
 the ship alluded to by the former. It is a matter of great regret
 that Lieut. de Roos has not presented us with the precise dimensions
 of these ships.

 [19] These dimensions carry the ratio of the length to breadth above
 4-1/3 to 1.

 [20] The French Admiral Willaumez, in his “Dictionnaire de Marine,”
 published in 1820, says under the article _Frégate_, that as far
 back as 1804, he had proposed a plan for a frigate of the largest
 size, with a round stern, wherein the quarter galleries were
 suppressed: the first frigate upon his plan was built at Brest about
 1821.

 [21] As the square root, so that to get _twice_ the velocity, _four_
 times as much canvas must be spread; and this is the most favourable
 estimate that can be made.

 [22] Vide Mr. Huskisson’s speech on the Shipping Interests.

[p039]




 _On Malaria_. No. II.

 [Communicated by J. Mac Culloch, M. D., F. R. S., &c. &c.]


Having pointed out, in the former paper on this subject, the nature
of the soils or places, of whatever description, by which malaria is
generated, it remains to notice a few other circumstances connected
with its natural history, a knowledge of which is essential for
the purposes of prevention; and finally to describe such modes of
prevention, applicable to these several circumstances, as have
been found useful in guarding against the attack of diseases from
this cause. Under the first head, there remain to be considered,
the effects of climate and season; the changes which occur in the
production and propagation of malaria, from various natural and
artificial causes; and also, the various modes in which it is
propagated.

It has already been remarked, that a certain elevation of temperature
was necessary to the production of this poison, though what the
precise degree is, has not been ascertained; and as this is, chiefly,
what distinguishes the regions or periods of the year which generate
malaria, I need not make two divisions of season and climate. If,
however, this temperature is not fixed, it will perhaps suffice
for our present purposes to say that the greater part of Scotland,
whether as to climate or season, seems incapable of generating the
disease from this cause; though there are exceptions of a permanent
nature, or exceptions of climate, as was perennially true of the
Carse of Gowrie before its drainage; while there are others which
happen when, as in the last year, there has been a peculiarly hot
summer, and which are exceptions of season.

And thus it is as to more northern regions; where a hot summer
becomes more than an equivalent for an average low temperature;
as an example of which, there is no place where intermittents are
more severe and abundant than at Stockholm. But the extreme of evil
from this cause occurs, as is well known, in the tropical climates;
appearing almost proportioned to the heat of the climate, and what is
important to observe to the moisture also. The destructive effects of
certain parts of Africa, India, America, and so forth, are familiarly
known; and [p040] it is in these countries especially, that the
diseases from this source constitute nearly the entire mortality of
the human race. And thus, for Europe, it is in Spain, Italy, and
Greece, and chiefly on their Mediterranean shores, that the activity
of malaria scarcely yields to that of the intertropical climates;
while in France, Holland, Germany, Hungary, and with us, in a far
less degree, the production will be found regulated by the heat of
the summers, all other circumstances being the same.

And if we thus account for the variations in the quantity and
virulence of diseases in any given country, for noted seasons of
epidemic in the countries which I have just named, and for the great
prevalence of fevers among ourselves during the last few years, and
particularly in the last summer, there is another point of scarcely
inferior importance to be taken into the consideration, independently
of that which relates to peculiar winds as connected with the
propagation of this poison;—and this is, moisture.

I need not repeat that water in some form is necessary to the
production of that peculiar vegetable decomposition which is the
source of this poison; and so true is this, that even in the
tropical regions, the diseases from this cause are nearly unknown in
districts of peculiar dryness, as they are in the drier seasons of
those countries. Thus, for example, Egypt is free from such fevers,
except at the period of the subsidence of the Nile, unless where,
as at Damietta, the cultivation of rice is pursued; and the same is
true of Mesopotamia very remarkably: and if I dare not extend these
illustrations, I must remark that in all these cases, the action of
moisture is twofold, inasmuch as it not only accelerates vegetable
decomposition, but renders the atmosphere a fitter conductor of this
poison.

Taking these two causes of the increase in the quantity and in the
action of malaria, we can explain many particulars which relate
to its power in producing diseases: and as the knowledge of these
is important as far as relates to the main object of this paper,
prevention, it becomes necessary to explain them at a little more
length.

As to season, the simplest case is that of the intertropical
climates; and Africa offers the plainest instance among the [p041]
whole. There, the malaria and the fever commence at the moment the
rain falls; diminishing as the ground becomes thoroughly wetted,
and recommencing as it dries. The explanation of all this ought to
be obvious; and the same analogy governs all the hotter climates,
as, though less conspicuously, it does our own. Hence we explain,
both as to our spring and our autumn, the effects of heat following
rain, or the reverse, and the diseases which are consequent on those
changes: and thus it is, though more remarkably, in Italy, that a
rainy autumn increases the number and severity of fevers; or, if the
summer has been unusually dry, that they often do not appear till the
commencement of the autumnal, or even the winter rains. And hence,
also, even with us, the occurrence of a single rainy day or week, in
the midst of the heats, will produce fevers; while the effect of this
influence is such, that should there even be an entire rainy summer,
and the subsequent one be hot and dry, this will be attended by an
unusual production of malaria and disease.

And if I cannot detail all the various modes in which these
circumstances may be modified, and how their effects may vary, it
will be useful to make one remark on an error as relating to it which
is universal among us, and into which even Lind has fallen. The error
is, to think that the rain, the moisture, or the cold is itself the
cause of the diseases which follow this state of things; while it is
obviously a case analogous to that of Africa, if less severe, and the
malaria is produced by these circumstances on soils which I formerly
pointed out, and which Lind, like every one else, had neglected. But
if I must pass over many interesting and useful conclusions to be
drawn from these general principles, there is one fact which I must
notice, and it is this:—

In spring, the combination of heat and moisture, easily explained,
generates, most commonly, intermittents; or the effect of the malaria
at this season differs from what it does in autumn: while as the
heat advances and the ground dries, this kind of fever ceases to be
produced, a new species, or the summer remittent, taking its place
when the heat and the moisture of autumn begin to act. But under
peculiar seasons of heat and moisture with us, it sometimes occurs,
as it has done [p042] within the last years, that the intermittent
season runs into the remittent one, or there is no midsummer interval
of freedom from disease; while it has also happened, and in some
parts of England in this last year, that what would have been
intermittent fever in other years has been remittent; or the common
fever has occupied the whole summer, continuously, even from March to
November, as is the case in the worst regions of southern Europe.

Now, under these exceptions, which I was bound to explain, the
commencement of intermittent, or of vernal ague, may be fixed about
the middle or end of March, and its termination similarly in May;
while that of remittent may be placed in the beginning of August,
and its termination with the middle or end of October. How these
periods may otherwise be affected by the more or less insalubrious
nature of the district or place, will easily be judged of by those
who will reflect for themselves on what I dare not explain, lest I
should infringe too far on my limits. All else that I can venture
on, as to this part of the question in hand, relates to the effects
of the different times of the day on the production, propagation, or
influence of malaria, and it is one which is of no small importance
in a practical view.

Whether the changes as to temperature and moisture which occur within
the space of twenty-four hours, affect the production or propagation
of malaria, I will not here inquire minutely, from the fear of
prolonging this very limited paper; but the general facts, as to its
effects, are these: If we commence with the sun on the meridian,
there appears, even in the worst climates, very little hazard of
fever; while in Italy, it is believed that there is, generally,
little or no hazard, except in some peculiarly pestilential places,
and under particular kinds of inattention or neglect. Either the
malaria is decomposed or destroyed by the heat, or else the air from
its dryness ceases to be a conductor; but as evening approaches,
its influence becomes powerful and dangerous, being supposed most
generally to extend all through the night; while in some parts
of that country it is a popular belief that it terminates before
midnight, or with the precipitation of the atmospheric moisture.
Whether this last opinion is true or not, the general fact explains
the popular [p043] belief, and truth, respecting the poisonous
effects of dew in the hot climates; the supposed pernicious quality
of this depending evidently on the malaria by which its formation is
accompanied. And in this case it is probable that the evil arises,
not from a fresh or peculiar generation of malaria, but from the mere
fact that the moist atmosphere is a better conductor than a dry one.

Not to be unnecessarily minute, we thus also explain the danger of
exposure to the morning air in similar situations; the facts, as
they relate to the conducting of malaria, being the same, though the
meteorological circumstances are somewhat different. Hence, also, we
see why the grey mists which hang over wet grounds in the evening
in our own climate, are esteemed pernicious; the truth, however,
being, that they are perfectly innocent at certain seasons and in
certain places—as in the greater part of Scotland, for example, or in
those places and at those periods where malaria is not produced. The
distinction is valuable, because of the inconvenience of restrictions
on this subject, and because to know where the hazard really lies
is to reduce those, and also to prevent the infraction of rules by
not extending them beyond what is necessary; and thus also by seeing
what are the real dangers of what is called night air, we more easily
avoid them. Night air is avoided now, under a false philosophy,
because it is cold or damp, or for some other vague reason; while
the dangers from mere dampness or cold are as nothing compared to
those here pointed out; which also occur precisely where they are
least feared, namely, in warm summer evenings, after refreshing
showers, and so forth. Hence it is that fevers are produced in
summer, in rural situations, and especially perhaps amid the most
engaging scenery, by evening walks and exposure to what is naturally
considered, as it is felt to be, a balmy and refreshing sequel to
a hot day. Let this be enjoyed where it can with safety, and as it
often may; but such evening walks will not be safe in any of those
situations which I need not repeat here; after having detailed them
as I have done in the former paper. And lest I should be accused of
wishing to excite unnecessary alarm, I consider, on the contrary,
that it ought to be diminished by these remarks; because, if we
take the whole of [p044] England, there is perhaps not one acre in
a hundred thousand where there is danger from night air, or from
malaria in any mode; so that to distinguish where that lies, is to
have relieved from useless fears all those who may learn to make the
distinctions under review.

To pass from what relates to climate and season, and to proceed to
the propagation, simply, of malaria, it is almost superfluous to
say, that its influence, as to the production of disease, is much
regulated by proximity, which implies a state of concentration or
accumulation. Hence the danger arising from vicinity; while, as I
formerly remarked, where the generating source is small, this becomes
necessary to its effect, since dilution may be expected to destroy
the power of the poison.

For analogous reasons, its effect in the production of disease is
increased by concentration or condensation; and such a state of
things takes place in narrow and confined valleys, or in places
surrounded by woods, or in woods themselves; in any situation, in
short, where the poison is produced, and is so sheltered from winds
that ventilation becomes difficult. And if it is probable that this
is one chief reason of the peculiarly insalubrious nature of woods
and jungles in hot climates, so is it an universal remark in Italy,
that the short valleys in which the air cannot circulate are among
the most pestilential spots. And if this explains, also, in some
measure, the bad effects of calm weather, so does it account for the
unusually pestiferous nature of rivers and lakes confined within
wood, as are those of the tropical climates, and as there are many
also in different parts of Europe. That we ourselves are not exempt
from these additional causes of the influence of malaria, would be
easily shown by many references, were it not for the reason which has
caused me to exclude them.

It is another important question for practice, how far and in what
manner malaria can be conveyed by the winds to places where it is not
produced, so as to act in exciting disease. That it is conveyed to
certain distances by winds is amply proved by an abundant experience,
and I may first detail a few of the most useful particulars as to
this fact. In Italy and Greece, it is observed, that where long
valleys terminate on sea shores, on which the exits of the rivers are
swampy, it is an [p045] effect of the sea breeze, by crossing such
marshy ground, to convey the malaria up into the interior country,
to considerable distances, and to places which are in themselves
not insalubrious. Thus, also, does such a breeze, especially when
it is a warm wind, convey the poison up the acclivities of hills,
even to a considerable range of distance or elevation; a process
facilitated by the natural tendency of such winds to ascend. And as
a striking proof of this migration of malaria, it appears from Capt.
Smyth’s statistical account of the insalubrious villages in Sicily,
that out of more than seventy, about one-half are not seated near or
on lands producing this substance, but on acclivities, at varying
distances—thus receiving it through migration. The same is remarked
by Montfalcon of many towns in France; while in some, the place at
a distance is even more unhealthy than that which is immediately
situated in the marsh itself: and in our own country, this is equally
said to be true of the backwater at Weymouth, and of the marshes of
St. Blasey in Cornwall, acting more powerfully at some distance than
in the immediate spot.

With respect to the absolute distance to which the malaria can be
conveyed, it is yet an obscure circumstance, or at least the maximum
has not been fixed; but it is at least ascertained that the convent
of Camaldoli receives it from the Lake Agnano, at a distance of three
miles; while from certain naval reports, a distance of five miles has
been proved to permit its transmission,—and from an evidence that
cannot be doubted, inasmuch as it was the sudden breaking out of
fever in a healthy ship, anchored at that distance from the shore,
on the coming off of the land wind, attended by its peculiar and
well-known smell.

These facts are satisfactory thus far, and it would be abundantly
easy to add to them; but there is reason to suspect that it can
be conveyed to far greater distances, in certain favourable
circumstances: those reasons, in the first place, being derived from
certain meteorological analogies and considerations, and in the next
confirmed by experience. It is notorious that the ague appears on
our eastern coasts with the first east winds of spring; and while
this circumstance is most common on those of England, as for example,
in Kent, Essex, Norfolk, [p046] Suffolk, and Lincolnshire, it is
not thus limited, since it is known to happen further north, and
even in Scotland, where malaria is not indigenous to the soil. It
is very true that if we take any inland position in the places thus
noted, the natural solution is, that the malaria is generated in the
very soil itself of England, and merely propagated, perhaps even to
very moderate distances, through those winds. But the occurrence of
disease cannot be explained thus, when the place in question is so
situated that there is no land to the eastward, or when the breeze
is, most literally and rigidly, a sea breeze; while, when ague thus
occurs on the east coast of Scotland, where it is not produced by the
soil, it must be imported by the east wind.

These are the facts; while as malaria is not produced by the sea
itself in any known circumstance, though a vegetating sea beach
may give rise to it, we must seek the cause in lands far distant,
and consider this as a case of propagation of the poison from the
shores of Holland; and those shores are unquestionably competent to
that effect: so that the only question that remains, the fact being
admitted, is, whether, _à priori_, or theoretically, such a view is
probable, or whether it is consistent with those physical principles
that are concerned in the propagation of malaria.

I am aware that such a view will excite the incredulity of those
who have not attended to this subject; though it appears to me that
it comprises nothing averse to our knowledge of the philosophical
circumstances concerned. In the first place, let us remark that the
east wind, and particularly the east winds of spring, are notorious
for their moisture, and that a moist air is the best conductor of
malaria, as moisture in the air, under the form of evening mists, or
in other modes, appears even to be its proper vehicle, or residence,
if I may use such a term; and though I have not as yet separated
the case of a fog, I may now remark, that the effect in question,
or the production of agues by fogs arriving from the sea, is even
more notorious than their generation by an ordinary clear wind. So
notorious and popular, indeed, is this fact, that the fog itself is
deemed the source of the disease, as the east wind under any form is,
in other circumstances; while I hope it will even now appear, [p047]
that the real cause lies in the malaria transported or conveyed
by those winds or fogs, and of which they are the true and best
repository and vehicle.

And these are the reasons for thinking that the malaria, with the
wind, may be transported to a distance as great as that which the
present view requires; most easily perhaps in a fog, but without
difficulty even in a clear wind. It is remarkable that the east wind,
as it is the most persevering, is that one also which preserves the
most steady horizontal and linear course. I have also shown, in a
former work, that it is a property of winds to travel in distinct
lines through a tranquil atmosphere, and often in streams of a very
limited breadth; that opposing streams will also move, in absolute
contact; and that even rapid streams of wind will cross each other’s
courses without difficulty. This proves that, in any such stream,
there is a principle of self-preservation or integrity, and renders
it probable that the several portions retain the same relative places
to each other, at any distance, during the career of the whole; and
there is a proof of this afforded in the fact of those columns or
streams of insects which are brought over by such winds, and very
frequently from those very countries, or from Holland and Flanders,
in the most regular order, or without disturbance or dispersion.

Hence it may be argued, that if a malaria, generated any where
and conveyed by the winds, can be transported to a distance of
three miles, as has been proved, there is no reason why it should
not travel much farther, or to any distance that can be assumed:
and if this be true of a clear wind, the case of a fog is even a
much stronger one; since there is little reason to doubt that the
individual parts of such fog, in any assumed mass, will retain their
relative places to each other, as perfectly after a journey of any
given number of miles, as they did at the point of production; and
if a portion of malaria has been united to a portion of fog, in the
marsh which produced both, or whence both have come, there is every
apparent reason why it should be found in that same portion at any
farther or assumed distance, because there is no cause for either its
dispersion or its decomposition.

A fog is a cloud, simply; and it is notorious that a single [p048]
cloud, and often of very small dimensions, will remain at rest
in the atmosphere, or travel very many miles without the loss of
its integrity; however we may imagine it assailed by the various
meteorological causes of destruction, as well as by mechanical
violence. This in itself proves the consistency with which a current
of wind preserves the relative positions of its integral parts;
because it is plain that a disturbance among these must disturb or
destroy the cloud which, in reality, forms a portion of that current,
as a gaseous body: and since that cloud is a mist, since it might
have been the very evening mist embodying a malaria, and since it
is its real vehicle and repository, it is plain that had it, or
any individual cloud, contained such a portion of malaria, it must
have had the power of transmitting that, and would actually have
transported it to any distance to which itself might travel. Thus, it
is evident, may a fog, generated in Holland, carry without difficulty
to the limits of its range, or to the coast of England, that malaria
which became entangled with it at its birth-place or in its passage;
and thus, I have little doubt, is the fact of those agues explained,
and this transportation to such distances established.

I cannot, at least, conceive any demonstration as to facts of this
nature more convincing, nor anything wanting to the proof; while
I may proceed to make some remarks on the east wind, and on fogs,
simply, because they concern this question.

The proof that it is a malaria in the fog, and not the fog itself,
which is the cause of disease, is evinced by the following fact;
while it ought surely to be unnecessary to say, that if fog alone
could produce such fever, water itself must be the poison: since a
fog is a cloud, and its constituents, when pure, are only atmospheric
air and water. No intermittents are ever produced on the western or
northern shores by the sea fogs, and for the plain reason, that there
is no land whence they arrive. The clouds of mountainous regions
do not produce fevers, though these also are fogs; and what forms
a most absolute proof of this is, that in Flanders, it is the fogs
which come with a southwest wind, or the southerly winds themselves,
which transport and propagate malaria and disease; while; as soon as
the winds shift, and blow from the sea, the fevers [p049] disappear,
though those particular winds are so charged with fog, as to darken
the whole country for days: and it will be found an invariable rule
all over the world, that when a fog is the apparent cause of disease,
or when an east wind is such, it is because these have been generated
in a land of marshes, or have traversed one; and that, under other
circumstances, or where no pernicious land lies in the way, they are
as innocent as any other fogs and winds, and that the hazard and the
suffering will arise from those, be they whatever they may, which
traverse pestilential lands.

But I must defer this particular and interesting subject to another
occasion, lest I make this article too long; and proceed to examine
some other circumstances connected with the transportation of malaria.

First, however, I must notice one fact as to this transportation from
Holland, partly because it is a necessary fact in the history of
malaria, and partly because it might be used as an argument against
the view which I have just given. The east winds of autumn are not
supposed to bring remittents, as those of spring bring agues, though
I cannot assert that this is absolutely true. Being assumed, the
solution is easy. If the winds of this nature in spring, are notedly
moist, and thus vehicles of malaria, the case is exactly the reverse
with the east winds of summer and autumn; or as the east wind may
be the most moist of winds, so may it be the most dry; while it is
a consequence of its extreme dryness, in fact, that it is always
the very cause of our burning summers. This is the history of our
last summers, and it is invariable, whether as it relates to seasons
or single days; and it is plainly owing to its permitting the more
ready transmission of the sun’s rays. That it is the very harmattan
of Africa, it is almost unnecessary to say; and as dry wind is not
a conductor of malaria, as that poison is in fact decomposed or
destroyed in these circumstances, daily and invariably, it is easy to
see why the remittents of Holland should not be transported, like its
intermittents, though even this may possibly happen under particular
circumstances.

To proceed; and to the next remarkable facts connected with the
propagation of malaria.—The most singular of these is its limitation,
or that yet unexplained property by which it is [p050] determined in
a particular direction, or confined to a particular spot, while it is
a piece of knowledge of some practical value. There is an appearance
of incredibility about many of these facts, and, accordingly, they
have not only been disbelieved but ridiculed, although nothing in the
whole history of this substance is better established.

With respect to direction, in the first place, it is remarked in
Italy, currently, that this poison will enter the lower stories of
houses, particularly with open windows, when the next above escape;
and hence, in many places, no one ventures to sleep on ground floors:
and the truth of this was confirmed in the barracks at Jamaica by Dr.
Hunter; as the cases of fever occurring among the men in the lower
rooms much exceeded those which happened in the upper ones. But I
am also informed, that in some places in Norfolk this peculiarity
is reversed; or that there are houses where it is remarked that the
ground-floors are safe, while no one can sleep in the upper stories
without hazard.

That malaria may in some manner be attached to the soil is also well
known by its effects, and especially in Italy. There it is remarked
that it is extremely hazardous to cut down certain bushy plants which
appear to entangle it, and that fevers are a frequent consequence of
such carelessness. Thus, also, does fever seize on the labourers who
may incautiously sit down on the ground, while they would escape in
the erect posture; being thus, indeed, sometimes suddenly struck with
apoplexy, which is one of the effects of this poison, or even with
death.

It has similarly been observed that it is often retained in the
shelter of drains, or in the ditches of fortifications; whence
frequent fevers among the sentries on particular guards, when the
other soldiers escape. And thus was it even proved at Malta, that it
was transported from the sea-shore, and thus lodged in a dry ditch of
the works at Valetta; all these facts being possibly to be explained,
by supposing it possessed of a greater specific gravity than the
atmosphere, or else attached to vapour thus weighty, exhibiting
effects analogous to those which carbonic acid displays in the
Solfatara.

But the circumstance most difficult of explanation is, that in
Rome, and numerous places in Italy, and even where it is [p051]
transported from a distance by the winds, not generated on the spot,
it is found, perennially, and through the whole course of successive
years, to occupy certain places, and to avoid, as constantly, others
quite near, and, as far as the eye can judge, equally exposed, and
in all respects similar. Thus, one side of a small garden, one side
of a street, or one house, will be for ever exposed to disease, or
uninhabitable, when, at a few feet or yards distant, the very same
places are as constantly free of danger: and thus it was found at the
village of Faro, in Sicily, that all the troops of our army quartered
on one side of the single street which formed it, were affected
by fevers, and suffered great mortality, while those on the other
remained in health.

But the most remarkable case of this nature known to me, is a
domestic one, and which rests on the testimony of thousands of
persons, or of the whole country, however incredible it may appear.
It is, that between Chatham and Brighton, including every town and
single house, and Sittingbourne among the rest, the ague affects the
left hand side of the turnpike road, or the northern side, and does
not touch the right side, though the road itself forms the only line
of separation.

We cannot as yet conjecture the cause of this very singular
circumstance or property, at least in cases of this nature;
though, under certain events of this kind, there are some facts
in meteorology that may offer a solution. These are the notorious
ones, that a hoar frost, or a dew, will sometimes be found most
accurately limited, both vertically and horizontally, by a definite
line; stopping, for example, at a particular hedge, and reaching to a
certain altitude on a tree: but for the other cases, we must yet wait
for a period of more accurate knowledge as to this singular substance.

There is now one circumstance of importance, relating to the
destruction or decomposition of malaria, which must not be passed
over, from the interest of the facts depending on it: this is,
that its propagation is checked by the streets of a crowded town,
and apparently owing to this very cause, decomposition. Thus it is
observed, that the fever never appears in the Judaicum of Rome, and,
similarly, that the crowded streets and the poor people escape, when
the opulent houses and open [p052] streets are attacked; and hence
the Villa Borghese, among many other palaces and opulent houses
in Rome, has been abandoned, while such desertion, being limited
exclusively to houses where the air is most open and free, naturally
excites wonder: the cause, however, is now plain; and thus it now
appears why it was that the Penitentiary in Westminster suffered
formerly from dysentery, originating in this cause, when no such
disease appeared among the neighbouring inhabitants.

And if this fact is of value as it may relate to the erection of open
streets in any place of this nature, it is most important to point
out what has been the continuous effect at Rome, as the ultimate
consequences threaten to be extremely serious.

It appears that from cutting down some forests which many years ago
occupied the declivities of the hills to the southward of Rome, the
malaria was let in upon that city from the Pontine marshes; and,
further, that the extirpation of a similar wood to the eastward had
let in the same poison upon another quarter. Thus it has been found
to enter the city through the Porta del Popolo, while, for many
years past, it has been gradually extending its influence through
the streets; leading annually and successively to the abandonment of
many houses and palaces, and still annually increasing and extending
its ravages; so as, at length, as I understand, to have even
become sensible at the Vatican. And the lines which it follows are
distinctly traced out by the inhabitants; while, as I have already
said, it is only the houses of the opulent which suffer, further than
as the abandonment of these may also influence the inferior ones in
their neighbourhood.

Whatever the original cause may be, and however the direction,
abstractedly, may be regulated by the winds and the forms of the
streets, or by local and fixed circumstances, it is plain that the
annual extension is the consequence of desertion, and that as the
inhabitants retire from before it, it acquires the means of making
a new step and a further progress; because thus they withdraw
those fires and smoke, or whatever else it be, dependent on human
crowds, which decomposes and destroys this substance. And hence it
must follow, that as Rome shall become still further abandoned and
depopulated, from want of industry, or from political feebleness
[p053] added to this cause, the effects must be expected to increase
in a sort of geometrical ratio; almost leading to the fear that
the whole city itself may, in time, fall a victim to it, or become
abandoned to the wolves and mosquitoes.

If I dare not inquire more minutely into the remaining circumstances
connected with the propagation of malaria, lest I should extend this
article to an inconvenient length, it is necessary now to offer
some remarks on prevention, and especially as it relates to this
circumstance—the propagation of the poison; since the rules for
prevention, as far as this relates to production, may be deduced from
what was said in a former paper on this subject, and relate chiefly
to the drainage of lands, and to other practices, more or less
obvious, which a little reflection will, without much difficulty,
deduce from what was there said.

It is plain, in the first place, that as far as the winds are
concerned, it is by opposing obstacles to their course that we must
attempt to counteract or divert their influence; and that, in this
case, it is through the use of trees alone that we possess any power.
Thus reversely, as in the case just stated, the cutting down of trees
and forests has often been a serious cause of diseases in certain
countries, by admitting a malaria to particular spots; though it is
easy to see that where any given spot suffers from malaria, through
condensation or confinement, the clearing away of these would be the
remedy, by attaining a free ventilation. To detail the particular
modes in which remedies may be applied through this species of aid,
is obviously unnecessary, and not easy, as it must depend on local
circumstances, differing for each place; but I may remark, as an
example in illustration of my meaning, that where, as in many of the
narrow and prolonged valleys of Greece, the sea shore is a marsh,
the remedy would be to plant a screen of trees beyond it, and thus
to prevent the sea winds from passing into the interior. And thus
did the ancient Romans compel the planting of trees on the shores
of Latium, to check the current from the Pontine marshes; rendering
groves sacred, under heavy penalties, and enacting other laws with
the same intentions.

With respect to such temporary precautions in these cases [p054] as
may concern armies in the field, or in camps, it is plain that they
will depend on attention to the courses and seasons of the winds;
while it would be abundantly easy to accumulate, from the histories
of campaigns, the most fearful examples of mortality produced by
neglect of these and similar precautions, and even down to almost
the very date at which I am writing: and there can be no hesitation
in saying, that an intimate and accurate knowledge of every thing
which concerns the production and propagation of malaria, forms a
most important branch in that information necessary to a soldier,
and above all to the quarter-master-general’s department and the
medical staff: while, did I dare to record but a very small portion
of the mortality experienced, not only in our own armies, but in
those of Europe at large, during even the last war, from ignorance
or neglect on this subject, it would, I believe, be found that it
almost equalled the mortality produced by the actual collision of
war itself. Walcheren will not soon be forgotten; if we have ceased
to think of our mortal Havannah expedition; and if a French army at
Naples was diminished by twenty thousand men, out of twenty-four, in
four days, from this cause; if Orloff lost nearly his entire army in
Paros; if Hungary has more than once destroyed ten times the number
of men by fever that it did by the sword,—these are but trifles in
the mass of reasons for saying, that no subject can well be more
important, and no knowledge much more necessary to the commander of
an army.

Some other points relating to prevention may deserve a few words
of notice, before I pass from this subject; if here, also, I must
be brief. Not to repeat the cautions founded on what relates to
the power of evening and morning, it has been asserted that the
use of a gauze veil will prevent the effect of malaria; and it is
not improbable that the air accumulated within that, may have the
power of decomposing the poison: it is an opinion, at least, which
is universal among the people in Malta, and very general in Spain
and Portugal. It is also found that fires and smoke are useful, and
especially on military service; the experiment having been tried on
a very large scale by Napoleon before Mantua, and on a smaller one
in Africa, with the most perfect success. With respect to [p055]
personal precautions, it is universally recommended to use wine and
a good diet, and especially never to leave the house in the evening
in situations peculiarly insalubrious, without the previous use of
wine or spirits; whence the universal practice of Holland in this
respect. Thus, also, narcotics prevent its influence; whence the wide
use of tobacco, of which the salutary effects appear to be most amply
established.

As to the tropical countries, there is here also one important
remark, which, from the great neglect of the fact, and its ruinous
consequences, appear particularly to demand a statement in this
place. It is the universal experience of the inhabitants, that the
attack of malaria, or the production of fevers, is aided by the use
of a full or animal diet; by the use of some particular articles of
food, such as butter; by excess in eating, generally; and, above all,
by eating in the heat of the day. This is not merely well known to
the negroes, but the fact is distinctly stated to travellers, and the
caution urged, however often it has been neglected, and especially
by our own countrymen. Of this, in particular, Major Denham is a
strong testimony; while he attributes his own exclusive preservation
to his having rigidly followed the recommendations of the natives,
which were always urged with the greatest earnestness. And if we
examine the causes of death, in most cases, of our African travellers
especially, I think there will be strong reasons for believing that
their lives have often been sacrificed to this very negligence
or obstinacy; while it is most evident that Niebuhr’s party, in
particular, owed the loss of their lives to what may be safely called
gluttony: and it is to be suspected that this will also explain the
loss of Captain Tuckey’s party; while, with respect to nations, it
has long been known that the English, the Dutch, and the northern
voracious people in general, who habitually indulge themselves in the
customs of their original country as tropical colonists, have always
been greater sufferers from the effects of those climates than the
French and the Spaniards, and apparently from this very difference.
And there seems little doubt, generally, that the vegetable diet of
Africa and Hindostan is the best security against the evil influence
of those climates, and that the chief sufferings of our [p056] own
colonists arise from transferring to those situations their ancient
habits of full and free living.

As I must not prolong this subject much further, I shall now pass to
a few remarks, but very brief ones, on the geography of malaria as
it relates to those parts of the continent of Europe most frequented
by English travellers; not daring to take room for actual and
useful information on that head, but wishing to point out merely
the importance of such geographical knowledge to those persons, on
account of the hazards which they so universally incur from that
ignorance or neglect, and of the great mass of suffering, and also
of mortality, which has been the lot of persons who had resorted to
those climates as travellers, or migrating residents, from various
motives, and not unfrequently with views to health. How often health
has been lost where it was sought, will be but too apparent to any
one who has chanced to possess an extensive acquaintance of this
nature.

Of Italy I can but afford to say generally, that except at a very
few points where the Alps or Apennines reach the sea, the whole of
its shores are pestilential, and often to such a degree as to lead
to their entire desertion, more frequently to their abandonment
in summer. And to avoid wet lands, or low lands, is not always a
sufficient precaution; since the most pestilential parts of the
maremma of Tuscany are dry, and since the annual mortality of Sienna
from fevers, even without epidemics, is one in ten. In the north of
Italy, the great plain is similarly insalubrious; though the more
unhealthy district does not commence until we arrive at Mantua,
extending thence to the sea. Of the Mediterranean islands, I can
only afford room to say, that the same rule holds good as to the
sea coasts, while the entire of Greece in the same circumstances
is similarly unhealthy, and subject to autumnal fevers in as great
a degree as the worst parts of Italy. The same is true of Spain
and Portugal, and the same rule also will be a guide; namely, that
malaria is to be expected in all the flat grounds, even when under
cultivation, and at all the exits of rivers on the sea, even though
no marshes should be present: and if I were desirous to name any
tract of land in Spain peculiarly [p057] insalubrious, it would be
the province of Valencia; while Carthagena is almost invariably fatal
even to those who, as labourers, are compelled to resort to it for
the needful work of its port, even during a few days.

Of France, little as it has hitherto been suspected by those who,
associating the term malaria with Italy, have been accustomed to
consider it as peculiar to that country, it would scarcely be untrue
to say that it contains as large a portion of insalubrious territory
as Italy itself, and produces fever and disease of as great severity
and extent, not merely on its sea coasts, but over very extensive
tracts in its interior. And this insalubrity may be conjectured,
when there are entire districts in which the average of life does
not exceed twenty, and in which the entire people are diseased from
their births to their graves. Such tracts are found chiefly on the
course of the Loire, and some other of the great rivers; and among
them, Bresse in the Lyonnais, the plain of Forez, and Sologne in the
Orleannais, are of the most notorious; while the coasts of Normandy,
and the whole of low Britanny, are similarly subject to eternal
intermittents, or to epidemic seasons of autumnal fevers, amounting
to absolute pestilences. And how English families have suffered in
this country from the incautious choice of residences in such places,
will be easily ascertained by whoever shall be at the trouble of
making the necessary inquiries.

But as I dare not pursue this extensive subject, I can only suggest
to our countrymen the utility of making themselves acquainted with
this matter, and with this dangerous geography, before encountering
the hazards which await them; while to physicians I need still less
name the necessity of that knowledge, since it is so often their
duty to choose and recommend for their patients, and since no man
can feel much at his ease who finds that he has sent into a land of
malaria the patient who has already been suffering from its diseases,
or that where he speculates on the cure of a consumption, that
cure is attained through the death of the patient, at Avignon, or
at Poitiers, or Nantes, or in some or other of the numerous places
subject to this most fearful poison.

It remains only to give a brief enumeration of the diseases [p058]
which are the produce of malaria, and of the general condition of
the inhabitants in the countries subject to it. With respect to this
latter, the most remarkable general fact is the contracted duration
of life. In England, the average may, if not very accurately, and
indeed considerably under the mark, be taken at 50; and when in
Holland it is but 25, it follows that the half of human life is
at once cut off by this destructive agent. In the parts of France
to which I have alluded, it becomes as low as 22 and 20, and
Condorcet, indeed, has calculated it as low as 18. With this, very
few attain the age of 50; and in appearance and strength, this
term is equivalent to 80 in ordinary climates; while 40 forms the
general limit of extreme and rare old age. The period of age, indeed,
commences after 20; and it is remarked, in particular, that the
females become old in appearance immediately after 17, and have, even
at 20, the aspect of old women. In many places, even the children are
diseased from their birth; while the life which is dragged on by the
whole population, is a life of perpetual disease, and most frequently
of inveterate and incurable intermittents, or of a constant febrile
state, with debility, affections of the stomach, dropsy, and far more
than I need here enumerate.

While the countenances of the people in those countries are sallow
or yellow, and often livid, they are frequently so emaciated as
to appear like walking spectres, though the abdomen is generally
enlarged, in consequence either of visceral affections or dropsy.
With these, rickets, varices, hernia, and, in females, chlorosis,
together with scorbutic diseases, ulcers, and so forth, are common;
and it is even to be suspected that the cretinage may depend on this
cause, since goitre is also one of the results of malaria, and since,
in the Maremma of Tuscany, idiotism is a noted consequence of this
pestilential influence.

The general mental condition is no less remarkable; since it consists
in an universal apathy, recklessness, indolence, and melancholy,
added to a fatalism which prevents them from even desiring to better
their condition, or to avoid such portion of the evils around them
as care and attention might diminish: and while it is asserted that
even the moral character becomes [p059] similarly depraved, I prefer
a reference to Montfalcon for a picture which it would not be very
agreeable to transcribe.

As to the absolute or positive diseases, besides those which I have
already named, I need scarcely say that remittent and intermittent
fevers, under endless varieties and types, form the great mass; and
next in order to them, may be placed dysentery and cholera, together
with diarrhœa. To these I must also add, those painful diseases of
the nerves, of which sciatica stands foremost, and the remainder of
which may be ranked under the general term of neuralgia; and further,
a considerable number of inflammatory diseases of a more or less
remittent type, among which rheumatism under various forms is the
most general, and the intermittent ophthalmia the most remarkable.
Lastly, I must include the various paralytic affections; since
apoplexy is one of the primary and direct consequences of malaria, as
various paralytic affections are the produce of intermittent, or the
consequences of the diseases of the nerves which are associated with
it.

It is still a curious and interesting fact, that this poison affects,
in an analogous manner, many different animals, and appears, in
reality, to be the cause of all the noted endemics and remarkable
epidemics which occur in the agricultural animals in particular.
This has been noticed even by Livy: and in France and Italy it is
equally familiar that the severe seasons of fever among the people
are similarly seasons of epidemics to black-cattle and sheep,
while the symptoms are as nearly the same as they could be in the
circumstances, and the appearances on dissection also correspond.
Thus also does it appear probable, that the rot in sheep is actually
the produce of malaria, as is indeed the received opinion among
French veterinarians; while Mr. Royston has observed that the animals
of this class are subject to distinct intermittents.

And while it is not less familiar in the West Indies, and in Dominica
particularly, that dogs suffer from a mortal fever in the same
seasons and periods as the people, the epidemic always breaking out
in them first, I have the most unexceptionable medical evidence of
the occurrence of a regular and well-marked tertian in a dog; that
evidence consisting in the concurring decision of many surgeons, by
whom the case was [p060] frequently examined, during a very long
period. But it is time to terminate a paper, which, if it is but a
sketch of an important subject, will at least convey to those to
whom malaria has not hitherto been an object of attention, a general
notion of the leading particulars which appertain to its natural
history.

 J. M.




 _Elements of Chemistry, including the recent Discoveries and
 Doctrines of the Science. By_ Edward Turner, M.D., F.R.S.E., &c.,
 &c. _Edinburgh_, 1827.


This is a closely-printed octavo of 700 pages, and presents us with
something more original, clear, and accurate than we have lately met
with in modern chemistry. It comprehends a perspicuous view of the
present state of chemical science; and, as far as its limits admit,
the theoretical parts are, with some exceptions, well and distinctly
worked out; nor are the practical details of manipulation neglected,
though they evidently occupy a secondary place in our author’s
estimation. To the arrangement we must at once decidedly object—it is
indeed evident that Dr. Turner has pitched upon Dr. Thomas Thomson
as his _magnus Apollo_, and here and elsewhere the book is tainted
accordingly.

This work is divided into four principal parts;—the first relates
to what Dr. Turner, following his prototype, Dr. Thomson, calls
_imponderables_, and a definition of them follows, which leads
us to suggest the term _inexpressibles_, as equally appropriate.
But, waiving this objection, the details relating to them are well
and clearly given. Thus, after some prefatory remarks upon the
subject of caloric or heat, (we prefer the latter term, and cannot
allow its ambiguity,) its modes of communication are considered,
first, as being _conducted_ through bodies, and then as _radiating_
through free space. In regard to the theories affecting the
latter, our author wisely, as we think, prefers that of Prevost
to that of Pictet. The _effects_ of heat are next discussed, such
as _expansion_, including an account of the thermometer, and
of the relative capacities of bodies for heat; _liquefaction_,
_vaporisation_, _ebullition_, _evaporation_, and the _constitution of
gases_ and lastly, the sources of heat are mentioned, but the details
are referred to other parts of the work. [p061]

_Light_ is next treated of, but we think too hastily, and too much in
the abstract.

Now the subjects of heat and light are obviously of the utmost
importance to the chemical philosopher, and they are very extensive,
and intricate and difficult to treat of, inasmuch as the writer is
necessarily upon the confines of chemical and mechanical philosophy,
and should be expert in both. When, therefore, elementary works on
chemistry are so written and arranged as to serve as text-books for
lectures, and indexes of reference to more accurate information, we
can make due allowance for brevity; but when the subject is intended
to be formally and completely developed to the student, independent
of other ocular and oral aids, much more extensive description and
detailed explanation is required, than is to be found either in
our author’s “Elements,” or in any other analogous condensation of
chemistry. Dr. Henry understands the requisite mode of conveying
information in these cases better than most writers; and when he
takes pains, and speaks for himself, has the talent of being brief,
and at the same time minute, deep, and clear. Dr. Ure, as his
dictionary shows, is an eminent example of such a writer—_he_ of
course is neglected, where, as with our author, Dr. Thomson is in the
ascendant; but the article caloric, in his dictionary, will at once
explain and illustrate our meaning, and would furnish an admirable
foundation for a detailed essay or treatise upon the subject. So
extensive, indeed, are the precincts of chemistry now becoming, that
either our _systems_ must become very voluminous, or we must adopt
the plan, which to us appears preferable, of distinct treatises upon
different branches of the science. Thus, a separate work on heat and
light; another on electricity and magnetism; another on attraction
and the theory of combination; a fourth on the constitution and
properties of the unmetallic elementary bodies; a fifth on the metals
and their compounds; a sixth on vegetable, and a seventh on animal
chemistry and physiology; an eighth on the chemistry of the arts;
and lastly, a treatise on chemical manipulation in general, would
include all that appears essentially requisite; and as no one is
supposed to be equally well versed in all branches of the science, or
in all details of the art, an opportunity of selection would thus be
afforded, so that each writer might choose that particular department
which he is most accurately acquainted with, or which has formed
his favourite study. Mr. Faraday has already, as may be said, led
the way in such a plan, by the publication of his _Chemical [p062]
Manipulation_, a work hitherto exceedingly wanted in the laboratory,
equally useful to the proficient and to the student, and eminently
creditable to the industry and skill of the author, and to the school
whence it emanates. We shall of course take an early opportunity of
introducing this book in a more formal way to the attention of our
chemical readers.

In looking over Dr. Turner’s first and second sections on caloric and
light, in the _Elements_ now before us, we find little but brevity
to complain of;—there are, however, one or two trifling historical
inaccuracies: thus, at page 14, the discovery of _invisible_ heating
rays is ascribed to Saussure and Pictet; but it is, in fact, of much
more remote origin—it was well known to the Florentine academicians,
and we may even trace the idea in Lucretius, (_De Rerum Naturâ_, lib,
v. 1, 609.)

 Forsitan et rosea Sol alte lampade lucens
 Possideat multum _cæcis fervoribus ignem_
 Circum se, _nullo qui sit fulgore notatus, &c._

At page 31 we have an account of Wedgwood’s pyrometer, which is said
to be “little employed at present, because its indications cannot be
relied on;”—the fact is, that it is never used, and that we owe to
Sir James Hall ample reasons for placing no confidence in it.

The subject of _specific heat_ is clearly explained, and so are
the phenomena of liquefaction and evaporation. In regard to the
constitution of gases, the author remarks, that the experiments
of Sir H. Davy and Mr. Faraday on the liquefaction of gaseous
substances, appear to justify the opinion that gases are merely the
vapours of extremely volatile liquids. Mr. Faraday has proved this
in regard to several of the gases, and analogy leads us to apply it
to the rest;—but what share Sir H. Davy had in the discovery, we
know not; for Mr. Faraday actually condensed chlorine into a liquid
before Sir H. had heard or thought about the matter. _Light_, and
its phenomena as connected with chemistry, is superficially passed
over in the second section, and the third brings us to the important
article “Electricity.”

We are willing to admit that the subject of electricity is a very
difficult one for the chemist to deal with—he must necessarily say
much upon it, and is equally obliged to omit abstract details which
are often necessary to its explanation, and yet too prolix and bulky
for an elementary chemical work. So that it requires considerable
acquaintance with the subject to give a perspicuous and yet concise
abstract, [p063] such as may be useful to the student. Dr. Turner
has not been very successful in effecting this _desideratum_, and
has unnecessarily introduced two sections, the one on electricity,
the other on galvanism. He also talks of the “science of galvanism,”
which is in bad taste, and erroneously asserts that the energy of the
pile is proportional to the degree of chemical action which takes
place; a statement by no means correct, inasmuch as the energy of De
Luc’s column is directly proportional to the number of alternations,
and appears entirely independent of chemical action; and again, a
series of 2000 plates, arranged in the usual Voltaic apparatus, when
perfectly bright and clean, and the cells filled with distilled water
only, give a much more powerful shock, and cause a greater divergence
of the leaves of the electrometer than when the apparatus is charged
with diluted acids. Here, those very singular phenomena, which
electricians distinguish by the terms _quantity_ and _intensity_,
appear perfectly distinct; and between these our author does not
sufficiently discriminate, but jumbles the whole under the term
_activity_. In describing the chemical energies, too, of the pile, or
its decomposing powers, the Doctor entirely overlooks the important
and curious influence of water. He says that acids and salts are all
decomposed, without exception, one of their elements appearing at one
side of the battery, and the other at its opposite extremity; (_i.
e._ we presume, at its positive and negative poles.) But the fact is,
that, excepting where it merely acts as a source of heat, nothing
is decomposable by electricity without the intervention of water;
the hydrogen and oxygen of which respectively accompany the elements
of the other compounds. Not an atom of potassium can be obtained
unless the potassa be moistened; nor can any salt be decomposed
except water be present. Sir Humphry says, it is required, to render
the substance a conductor; but its operation is more recondite, and
there is something mysterious and still unexplained in the uniform
appearance of hydrogen and oxygen at the opposite poles, when far
apart in water, and in all other cases of true polar electro-chemical
decomposition. At page 86, the unfortunate protectors of ships’
bottoms are introduced—a subject about which the less is said the
better;—and, as to electro-magnetism, it is merely mentioned as to
its leading phenomena, in the space of three or four pages; nor
is anything new suggested upon the “Theory of the Pile,” as it is
called, which concludes the subject, and which is dismissed in the
brief limit of a page and a half. [p064]

The second part of Dr. Turner’s work is said to comprise “Inorganic
Chemistry,” and therefore embraces a very extensive field of inquiry.
To the _arrangement_ we have already objected; and many of the
typographical and verbal errors that occur, have been noticed in a
contemporary Journal, so that we shall chiefly attend to the details
of the sections.

Under the head, “Affinity,” some of the leading facts and doctrines
of chemical attraction are perspicuously set forth; but we could have
wished that a variety of exploded opinions and erroneous notions had
been altogether passed over, as they occupy space which might have
been better employed, and can never prove of any other use to the
student than to show him the errors and fallacies to which acute
philosophers are sometimes liable. Of this kind, especially, are
Berthollet’s notions upon the subject of affinity. The doctrine of
definite proportion is, on the whole, well and clearly explained; but
it would have been much better and clearer, had Dr. Turner confined
himself to facts, and meddled less with opinions concerning their
cause; he is moreover, in many respects, historically inaccurate. He
ascribes much to Dalton that honestly belongs to Higgins;—is much
too merciful to Berzelius and his CANONS; and lenient beyond all
endurance to the plagiarisms of “Dr. Thomson’s admirable Treatise on
the first Principles of Chemistry.”

In the third and following sections, the simple non-metallic
substances are described in an order of arrangement which must be
very perplexing to the student; otherwise the details are well
given, except that here and there the line between theory and fact
is not sufficiently marked. Thus we are told that “hydrogen is
exactly 16 times lighter than oxygen, and _therefore_ that 100 cubic
inches _must_ weigh 33.888/16, or 2.118. Its specific gravity is
consequently 0.0694, as stated some years ago by Dr. Prout.” Now this
is a theoretical deduction, founded upon the specific gravity and
constitution of ammonia, (and not upon the composition of water,) and
probably correct as applied to _pure_ hydrogen;—but if we weigh the
gas, as usually obtained, even with the utmost caution, and of the
utmost purity, we shall never procure it so light as here stated,
notwithstanding all the learning and argument that our worthy friend,
Dr. Thomas Thomson, has issued upon the subject in his various
essays in the Annals, and in his _magnum opus_. We also object to
the stress which is often laid upon the whims of individuals, and
upon [p065] exploded opinions; instances of which will occur to the
reader under the subject of the composition of nitrogen, and the
constitution of the atmosphere. We further caution our author against
admitting hints, allusions, and inuendos as to the possibility of
future inventions and discoveries, as claims upon the merits of such
discoveries, when they are actually made. Berzelius has talked a vast
deal of nonsense about the composition of nitrogen; and should that
discovery ever be made, he will doubtlessly assume the credit of
having suggested the steps which led to it. Some foolish persons are
apt to think that the Marquis of Worcester was the inventor of Watt’s
steam-engine, because he said he had means of raising water by steam,
in his _Century of Inventions_; and we have heard that an eminent
chemist of the present day considers himself entitled to all the
merit that may belong to Mr. Brunel’s carbonic acid engine, because
he had previously stated the possibility of such an application of
Mr. Faraday’s important discoveries. The fact is, that these are
woeful days for science; all the good feeling and free communication
that used to exist among its active cultivators in this country, has
given way to petty jealousies and quibbling scandal; one person is
exalted for the purpose of depreciating another; and those causes of
disgust, which some years ago induced one of our most amiable and
able men of science to quit the field, and even leave the country,
are becoming daily more prevalent. Were it not an invidious task, we
could easily explain and unfold the sources of all this mischief, and
shall indeed feel it our duty so to do, should not matters in due
time take a more favourable turn; but the task is at once serious
and disagreeable, and we therefore postpone it, in the hope of more
favourable events. We really believe that, had it not been for the
scientific conversationes held during the last season at the houses
of a few private gentlemen connected with the learned societies,
and more especially the weekly meetings at the Royal Institution,
which kept up a friendly intercourse among those who were willing
to profit by it, that the whole scientific world would have been at
loggerheads, and in that state of anarchy of which the evils may be
learned by a short residence at a “northern seat of learning.”

The main object of this digression is to deprecate _party_ in
science; and we were led to it by observing, or thinking that we
observe, something of such a tendency in the writer whose book is
before us—we hope we are mistaken.

The next section comprises “the compounds of the simple [p066]
non-metallic acidifiable combustibles with each other.” It includes
the important subject of ammonia, of the varieties of carburetted
hydrogen, sulphuretted and phosphuretted hydrogen, and cyanogen
and its compounds. The metals are then treated of, and to these
succeed their salts; and though the execution of this part of the
work betrays some haste, it shows also considerable reading, and
some originality: the general views are well and clearly sketched,
but there are many points upon which we are entirely at variance
with our author; and we more especially object to his account of the
action of chlorides upon water, and to his notions concerning the
“muriates of oxides,” a class of compounds of which, with one or two
exceptions, we are disinclined to admit the existence. If common
salt be a _chloride_ of _sodium_, and experiment obliges us so to
regard it, what is there in its aqueous solution that should lead us
to consider it as containing a _muriate_ of _soda_; what evidence of
any new arrangement of elements? Dr. T. is certainly in mistake, when
he says, “for all practical purposes, therefore, the solution of a
metallic chloride in water may be viewed as the muriate of an oxide,
and on this account I shall always regard it as such in the present
treatise.” This inconsiderate dogma taints much of the reasoning
upon the chlorides, &c., and is manifestly culled in the Thomsonian
school, though we have indeed heard that a Professor at Edinburgh
thus addresses his pupils upon the above subject: “The elaborate
researches of the illustrious Davy have taught us that common salt
is a binary compound of chlorine and sodium, a chloride, therefore,
or a chloruret of sodium. But it is only chloride of sodium whilst
quiescent in the salt-cellar; for no sooner does it come into
contact with the salivary humidity of the fauces, than, by the play
of affinities, which I have elsewhere explained, the sodium becomes
soda, and the chlorine generates muriatic acid;—that, therefore,
which upon the table is chloride of sodium, is muriate of soda in
the mouth; and this again, when desiccated or deprived of humidity,
retrogrades into its former state.”

Dr. Turner again falls into error, as we humbly conceive, in calling
certain salts, such, for instance, as those of the peroxide of iron,
_sesquisalts_, a term properly applied in those cases only where one
proportional of a protoxide unites with one and a half of an acid,
such for instance as the _sesquicarbonate of soda_, &c., but in the
sesquisulphate of iron, one proportional of the peroxide contains
1.5 of oxygen, and [p067] necessarily, therefore, (according to
Berzelius’ canon, if the Doctor pleases,) requires 1.5 of acid to
convert it into a salt; just as the commonly constituted peroxides
(containing two proportionals of oxygen) require two of acid. Dr.
Thomson, with all his nomenclatural pretensions, has fallen into the
same error.

The part of our author’s work which treats of the chemistry of
organic bodies is, upon the whole, an unexceptionable and accurate
epitome of that complicated branch of the science. It has its
inaccuracies, but they apparently arise out of the difficulty of
condensing into the space of a few pages, matter which, as we have
elsewhere remarked, would require an ample volume for its extended
and perspicuous details.

In our hasty account of this work, we have rather dwelt upon its
defects than its merits, in the hope of seeing another and more
extended edition, free from what we consider as serious obstacles
to the success and usefulness of the present production. We hope
that Dr. Turner will not feel offended at the freedom with which
our remarks are offered. We are anxious that a writer of such good
information should be induced to think for himself; at least, that
he should accurately weigh the pretensions, and inquire into the
originality of those views and researches upon which he bestows such
unqualified and, in our opinion, undeserved praise, and to which he
assents with a facility unbecoming one who evidently possesses the
means of testing their merits.




 _Experiments on Audition_.

 [Communicated by Mr. C. Wheatstone.]


The recent valuable experiments of Savart[23] and of Dr. Wollaston
have added to our stock of information several important and
hitherto unnoticed phenomena relating audition; but, notwithstanding
the investigations of these distinguished experimentalists, and
though the physiology of the ear has been an object of unceasing
attention for many centuries, yet we are far from possessing a
perfect knowledge of the functions of the various parts of this
organ. The description of new facts illustrative of this subject
cannot, therefore, be devoid of interest; [p068] and though I do not
anticipate that the observations contained in this communication will
lead to any important results, their novelty may claim for them some
attention from the readers of your Journal.

 § 1.

If the hand be placed so as to cover the ear, or if the entrance
of the meatus auditorius be closed by the finger without pressure,
the perception of external sounds will be considerably diminished,
but the sounds of the voice produced internally will be greatly
augmented: the pronunciation of those vowels in which the cavity of
the mouth is the most closed, as _e_ _ou_, &c., produce the strongest
effect; on articulating smartly the syllables _te_ and _kew_, the
sound will be painfully loud.

Placing the conducting stem of a sounding tuning-fork[24] on any part
of the head, when the ears are closed as above described, a similar
augmentation of sound will be observed. When one ear remains open,
the sound will always be referred to the closed ear, but when both
ears are closed, the sound will appear louder in that ear the nearer
to which it is produced. If, therefore, the tuning-fork be applied
above the temporal bone near either ear, it will be apparently heard
by that ear to which it is adjacent; but on removing the hand from
this ear (although the fork remains in the same situation) the sound
will appear to be referred immediately to the opposite ear.

In the case of the vocal articulations, the augmentation is
accompanied by a reedy sound, occasioned by the strong agitations
of the tympanum. When the air in the meatus is compressed against
this membrane by pressing the hand _close_ to the ear, or when
the eustachian tube is exhausted by the means indicated by Dr.
Wollaston, the reedy sound is no longer heard, and the augmentation
is considerably diminished. The ringing [p069] noise which
simultaneously accompanies a very intense sound, proceeds from the
same cause, and may be prevented by the same means. This ringing may
be produced by applying the stem of a sounding tuning-fork to the
hand when covering the ear, or by whistling when a hearing trumpet
is placed to the ear. As a proof that the resulting augmentation,
which, when great, excites the vibrations of the tympanum, is owing
to the reciprocation of the vibrations by the air contained within
the closed cavity, it may be mentioned, that when the entrance of the
meatus is closed by a fibrous substance, as wool, &c., no increase is
obtained.

If the meatus and the concha of one ear be filled with water, the
sounds above-mentioned will be referred to the cavity containing the
water in the same way as when it contained air, and was closed by
the hand; it will be indifferent whether any partition be interposed
between the cavity and the external air; as the water is equally well
insulated by a surface of air as by a solid body.

 § 2.

The preceding experiments have shown, that sounds immediately
communicated to the closed meatus externus are very greatly
augmented; and it is an obvious inference, that if _external_ sounds
can be communicated, so as to act on the cavity in a similar manner,
they must receive a corresponding augmentation. The great intensity
with which sound is transmitted by solid rods, at the same time that
its diffusion is prevented, affords a ready means of effecting this
purpose, and of constructing an instrument, which, from its rendering
audible the weakest sounds, may with propriety be named a Microphone.

Procure two flat pieces of plated metal, each sufficiently large
to cover the external ear, to the form also of which they may be
adapted; on the outside of each plate directly opposite the meatus,
rivet a rod of iron or brass wire about 16 inches in length, and
one-eighth of an inch in diameter, and fasten the two rods together
at their unfixed extremities, so as to meet in a single point. The
rods must be so curved, that when the plates are applied to the
ears, each rod may at one end be perpendicularly inserted into its
corresponding plate, and at the other end may meet before the head in
the plane of the mesial [p070] line. The spring of the rods will be
sufficient to fix the plates to the ears, but for greater security
ribands may be attached to each rod near its insertion in the plate,
and be tied behind the head.

 [Illustration: untitled, Microphone]

A more simple instrument may be constructed to be applied to one ear
only, by inserting a straight rod perpendicularly into a similar
plate to those described above.

The Microphone is calculated only for hearing sounds when it is in
immediate contact with sonorous bodies; when they are diffused by
their transmission through the air, this instrument will not afford
the slightest assistance.

It is not my intention in this place to detail all the various
experiments which may be made with this instrument, a few will
suffice to enable the experimenter to vary them at his pleasure.

1. If a bell be rung in a vessel of water, and the point of the
microphone be placed in the water at different distances from the
bell, the differences of intensity will be very sensible. 2. If
the point of the microphone be applied to the sides of a vessel
containing a boiling liquid, or if it be placed in the liquid itself,
the various sounds which are rendered may be heard very distinctly.
3. The instrument affords a means of ascertaining, with considerable
accuracy, the points of a sonorous body at which the intensity of
vibration is the greatest or least; thus, placing its point on
different parts of the sounding board of a violin or guitar, whilst
one of its strings is in vibration, the points of greatest and least
vibration are easily distinguished. 4. If the stem of a sounding
tuning-fork be brought in contact with any part of the microphone,
and at the same time a musical sound be produced by the voice, the
most uninitiated ear [p071] will be able to perceive the consonance
or dissonance of the two sounds; the roughness of discords, and the
beatings of imperfect consonances, are thereby rendered so extremely
disagreeable, and form so evident a contrast to the agreeable
harmony and smoothness of two perfectly consonant sounds, that it is
impossible that they can be confounded.

 § 3.

Apply the broad sides of two sounding tuning-forks, both being
unisons, to the same ear; on removing one fork to the opposite ear,
allowing the other to remain, the sensation will be considerably
augmented.

It is well known, that when two consonant sounds are heard together,
a third sound results from the coincidences of their vibrations;
and that this third sound, which is called the grave harmonic, is
always equal to unity, when the two primitive sounds are represented
by the lowest integral numbers. This being premised, select two
tuning-forks, the sounds of which differ by any consonant interval
excepting the octave; place the broad sides of their branches, while
in vibration, close to one ear, in such a manner that they shall
nearly touch at the acoustic axis, the resulting grave harmonic will
then be strongly audible, combined with the two other sounds; place
afterwards one fork to each ear, and the consonance will be heard
much richer in volume, but no audible indications whatever of the
third sound will be perceived.

 § 4.

Very acute sounds, such as the chirping of the gryllus campestris,
&c., are rendered inaudible by exhausting the air from the Eustachian
tube, and thereby producing a tension of the membrane of the
tympanum; the different thicknesses or tensions of this membrane
may therefore occasion that diversity of the limits of audibility,
with regard to the acute sounds which Dr. Wollaston has pointed out
as existing in different individuals; if so, it would be desirable
to ascertain this limit in individuals in whom the tympanum is
perforated, or destroyed.

 § 5.

When the auricula is brought forward, all _acute_ sounds are rendered
much more intense, but no sensible difference is [p072] perceived
with regard to the grave sounds. The _higher_ tones of glass
staccados, or of an octave flute, the ticking of a watch, all kinds
of sibilant sounds, &c. are thus greatly augmented: the experiment
is easily tried, by whistling very shrill notes. A still greater
augmentation of the acute sounds is obtained, by placing the hands
formed into a concave behind the ears, and by bending downwards the
upper part of the auricula, so as to obtain a more complete cavity.

 § 6.

I will conclude with the following observation: I had, in consequence
of a cold, a very slight pain in my left ear; on sounding the regular
notes of the piano-forte, C^3 and C^4 were much louder than the
others, and the loudness was much increased, by placing the hand
in the manner above described to the left ear. When it was pressed
close, or when the Eustachian tube was closed, the intensities of
all the notes were equalized. I attribute this affection to the
diminished tension of the membrana tympani, which was again increased
by the operation described.


 FOOTNOTES:

 [23] Recherches sur les usages de la membrane du tympan et de
 l’oreille externe; par M. Felix Savart. _Annales de Chimie_, tom.
 xxvi. p. 1.

 [24] The tuning-fork consists of a four-sided metallic rod, bent so
 as to form two equal and parallel branches, having a stem connected
 with the lower curved part of the rod, and contained within the
 plane of the two branches. The branches are caused to vibrate by
 striking one end against a hard body, whilst the stem is held in the
 hand. The sound produced by this instrument when insulated is very
 weak, and can only be distinctly heard when its branches are brought
 close to the ear; but instantly its stem is connected with any
 surface capable of vibrating, a great augmentation of sound ensues
 from the communicated vibrations. The facility of its insulation and
 communication renders it a very convenient instrument for a variety
 of acoustical experiments.




 _On the Petromyzon Marinus_.


On entering the harbour of Dublin a few weeks ago, we were becalmed
off the Hill of Howth, and to pass the tedious time until a breeze
sprung up, we found some lines on board, and began to fish from the
quarter-deck. We caught a number of grey gurnet; but our attention
was particularly attracted by a pull of uncommon force on one of
the lines. Having rendered assistance to the person who held it, we
were all astonished to see rise out of the water a large fish, with
apparently a double body, which, after floundering on the surface
of the water, we pulled on deck. On examining this phenomenon for
a short time, we were again surprized to see it separate into two
parts; and then found that there were _two_ large fish taken up on
the same hook, the head of one having been buried under the throat
of the other, to which it had firmly attached itself. When separated
by force, it wiggled about on the deck with extraordinary strength
and agility, and again darted on its prey, to which [p073] it adhered
so firmly, that it required very considerable exertion to detach
it; for it suffered itself to be raised up by the tail, and shaken,
still holding the other fish suspended from its jaws. When finally
separated, it showed great ferocity, darting at every thing near it,
and at last seizing the deck, which it held very fast, writhing with
its tail and body as if in the act of tearing it to pieces. When
detached, its teeth left a deep circular impression on the wood, the
fibres of which were drawn into the cavity of its jaws, so as to be
raised up in the form of a cone. I now directed, that it should be
put into a bucket of sea water, in the hope of preserving it alive
until we arrived in Dublin, but it died in a shorter time than could
be expected, from the energy and activity it had displayed, long
after the other fish was dead. We had handled it very roughly, and so
perhaps had mortally hurt an animal otherwise very tenacious of life.

 [Illustration: untitled, Fish]

On examining the fishes, I found that which had taken the hook,
was the _gadus Polachius_, or whiting Pollack. It was about two
feet long, and it is probable its active enemy had fastened [p074]
on it after it had been hooked; if _before_, it would indicate an
extraordinary insensibility to pain in an animal that could attend to
the calls of appetite, whilst another was preying on its vitals. The
fish which had fastened on the pollack, was the _petromyzon marinus_,
or sea lamprey. It was nearly three feet long, and resembled a large
eel in shape. Its general colour was a dull brownish olive variegated
with bluish blotches; the back darker, and the belly paler, inclining
to yellow. The eyes were small, and the mouth large and oval; but
when distended, circular. The inside of the jaws was deeply concave,
and studded with circular rows of sharp triangular teeth, that issued
from corresponding orange-coloured papular protuberances, which
formed the gums; the tongue was short and crescent-shaped, furnished
with a row of very small teeth round the edge. On the top of the
head was a small orifice, or spout-hole, from whence it discharged
the superfluous water taken at the mouth. But the circumstance that
more particularly distinguished it, was that which gave rise to the
vulgar error that it had sixteen eyes. On either side of the neck,
commencing just below the real eyes, was a row of seven equidistant
spiracles exactly resembling eyes; they are, however, holes lined
with a red membrane, and all opening into the mouth, an apparatus to
supply the place of gills, whose functions are to extract oxygen from
the water, and so perform the office of lungs in aquatic animals. It
had two dorsal fins, one on the lower part of the back, narrow, with
a roundish outline; the other commencing where the first terminated.
The spine was cartilaginous, without processes. The pericardium,
containing a small heart, was a remarkably strong membrane, and the
liver was as green as grass.

This fish is not uncommon in the North Seas, though it most abounds
in the Mediterranean, where, from earliest times, it was esteemed a
luxurious dish. Fish-ponds were purposely constructed to preserve
it. On our coast, Pennant observes, that it is found most frequently
at the mouth of the Severn, which river it sometimes ascends, where
it is occasionally taken, firmly attached to a stone by its mouth,
while its tail and body are waving freely to the current. Its
adhesion at such times is so strong, that it may be lifted with a
stone of twelve pounds weight appended to its mouth. This faculty
is owing to its [p075] power of suction; while the circumstance of
its circular jaws coming in close contact with the surface of the
body excludes the external air within the cavity of the mouth, and
so adheres like the hand placed on the cup of an air-pump. It is
from this remarkable property, that its scientific name has been
imposed[25]. Its vulgar name, lamprey, from lampetra, has a similar
derivation. By the Romans it was named muræna. As this fish was well
known and highly prized by the ancients, there is none that has been
so frequently described and alluded to. Aristotle, Pliny, Tacitus,
Columella, Ælian, Seneca, and Oppian, have mentioned its properties
and habits, which correspond exactly with those I have described
above. Pliny says, in the northern parts of France, and consequently
contiguous to the British Isles, the lampreys have seven spots in
the jaws, resembling the constellation of the plough, evidently the
same as the eyes, which vulgar opinion assigns to the fish[26]. Their
extreme voracity was such, that criminals were thrown among them to
be devoured. Seneca relates, that Vedius Pollio, a Roman knight,
ordered his servant, who had broken a crystal vase, to be thrown into
a large pond of lampreys[27]; and Columella writes, that they were
sometimes seized with a rabid fury, that resembled canine madness;
in the access of which, they seized upon other fish, so that it was
impossible to keep them in the same pond[28]; and to account for this
extraordinary ferocity, Oppian and others assert, that the lamprey
is impregnated by a serpent; the one issuing from the sea, and the
other rushing down to the rocks, inflamed with madness, to consummate
the impregnation; and adds, that the extraordinary intercourse was
effected by the lamprey seizing the serpent’s head in its [p076]
mouth[29]. This singular copulation was the reason why the Romans,
who were immoderately fond of lampreys, did not wish to eat them,
when impregnated by the supposed serpent. Horace, therefore, makes
Nasidienus, among the blunders of his supper, serve it in that
state[30].

Lampreys were a favourite dish with our own early monarchs. Henry
II. died by eating them to excess. The celebrated Pope also owed his
death to a surfeit of them. Doctor Johnson remarks in his life of the
poet, that he was in the habit of cooking them himself in a silver
saucepan. The Corporation of Oxford still make up a periodical pye
of this fish for the king, in compliance with ancient usage. But
lampreys have lost their rank at corporation feasts, in consequence
of the more delicious and wholesome turtle being introduced into
modern cookery.

I have never noticed lampreys in the Dublin fish-market; and though
they are frequently used in the South of Ireland, I do not know if
they have ever been made an article of food in Dublin, or the north,
where they are rarely met with.

 C.


 FOOTNOTES:

 [25] Petromyzon, _a_ πετρον, saxum, and μυζαω, sugere.

 [26] In Gallia septentrionale murænis omnibus dextra in maxilla
 septenæ maculæ ad formam septentrionis aureo colore fulgent. PLIN.
 _Hist. Nat._ lib. ix. cap. 39.

 [27] Fregerat unus ex servis crystallinum ejus; rapi eum Vedius
 jussit, nec vulgari quadam morte periturum, murænis objici jubebatur
 quas ingens piscina continebat.—SENECA _de Irâ_, lib. ii. cap. 40.

 [28] Commisceri eas cum alterius notæ piscibus non placet, quasi
 rabie vexantur quod huic generi velut canino solet accidere. Sævitia
 persequuntur squamosos plurimosque mandendo consumunt. COLUMELLA _de
 Re Rusticâ_, lib. ix. cap. 17.

 [29]  Αμφι δε μυραινης φατις ερχεται ουκ αιδηλον
       Ὥς μεν γαμει τε και εξ ἅλος ερχεται αυτη
       Προφρων ἱμειουσα παρ’ ιμειροντι γαμοιο
       Ητοι ὁ μέν φλογεῃ τεθοωμενος ενδοθι λυσσῃ
       Μαινεται ἔις φιλοτητα και ἔγγυθι συρεται ἅκτης
       Πικρος ὄφις. κ.τ.λ.—OPPIAN, _Halieut._ lib. i. V. 554.

 [30] Adfertur squillas inter muræna natantes, In patinâ porrecta:
 “hæc gravida,” inquit, “Capta est.”—HOR. lib. ii. Sat. 8. lin. 46.




 _Observations upon the Motion of the Leaves of the Mimosa Pudica_.
 [To the Editor of the Quarterly Journal of Science.]


 Dear Sir,

Towards the latter part of this summer, Mr. Gilbert Burnett and
myself made several experiments with a view to ascertain the nature
of the movements exhibited by the sensitive plant. We afterwards
found that the greater part of the facts which we had observed, had
been previously described by Mr. Lindsay [p077] and Dr. Dutrochet.
Mr. Lindsay’s observations are to be met with in a MS. preserved in
the library of the Royal Society, which is dated July 1790: this
essay is alluded to by Dr. Smith in his “Introduction to Botany.”
Dr. Dutrochet’s experiments were published in his “Recherches
anatomiques et physiologiques sur la Structure intime des Animaux
et des Végétaux,” which appeared in 1824. With the latter author
the reputation of originality is likely to rest: not undeservedly,
indeed, as there is no reason to suppose that _his_ experiments
were suggested by a knowledge of those performed by Lindsay. It
is, however, an act of literary justice to secure to Mr. Lindsay
the credit of undoubted priority in describing the phenomena which
he noticed in common with Dutrochet. I have drawn up the following
remarks partly for this purpose—partly to have an opportunity of
mentioning some circumstances which escaped the observation of both
experimentalists.

The leaves of the Mimosa Pudica consist either of one or two or
three pairs of leaflets, and occasionally terminate by an odd
one. Each leaflet bears from twenty to sixty subleaflets, which
are disposed in pairs. The petiole or stalk of each leaf, at the
extremity which is attached to the branch or stem of the peant,
swells into an intumescence varying from three to five in length. A
similar intumescence, of proportionate dimensions, is seen upon each
subpetiole, where it is articulated with the petiole, and upon the
base of the stalk of each subleaflet: the intumescence is the part in
which motion takes place.

During the day-time the petioles are observed to have a direction
upwards, or rather to form an acute angle with the upper part of
the stem or branch, to which they are attached: the subpetioles are
divergent: the subleaflets are spread out, so as to lie nearly in one
plane. (_Fig._ 1.)

During the night the petioles are found to be depressed; the
subpetioles to be drawn together, the subleaflets folded, the upper
or solar surfaces of each pair being brought into contact. (_Fig._ 2.)

The leaves rise, the leaflets diverge, and open by throwing down
their subleaflets, at daybreak: the opposite changes occur about
sunset. The experiments that are to be described, are supposed to be
performed in the day-time. [p078]

 [Illustration: _Fig._ 1.]

If a terminal subleaflet be pinched with forceps, or cut with
scissors, it rises, together with its fellow; then the next pair
rise; then the next; and so on in succession, till all the pairs of
subleaflets upon the same subpetiole are folded. In a little time
afterwards, the petiole is bent downwards at its intumescence; and in
a few seconds more the remaining leaflets upon the same petiole fold
their subleaflets in pairs, from the base towards the point of the
leaflet.

 [Illustration: _Fig._ 2.]

If a subleaflet be burnt, instead of being cut or pinched, the
phenomena above described occur more rapidly: and after they have
taken place, the adjoining leaves upon the same branch are bent down
in succession, their leaflets brought together, and their subleaflets
folded. If the plant be very vigorous and lively, an impression
[p079] made upon one leaf affects the rest in succession. It is well
known that the stem, branches, flowers, and roots of the sensitive
plant have no motion. But M. Desfontaines observed that, on touching
the roots with sulphuric acid, the leaves become folded; and M.
Dutrochet obtained a similar result on burning either the flower or
the stem.

 [Illustration: _Fig._ 3.]

 [Illustration: _Fig._ 4.]

 [Illustration: _Fig._ 5.]

If the plant be shaken, all the leaves are simultaneously thrown
down, and their leaflets folded. Mr. Lindsay attempted to elucidate
the action of the intumescence in raising and depressing the petiole,
in the following manner. He cut out a portion from the upper or solar
surface of the intumescence; after which he found that the petiole,
upon recovering, rose higher than before, (_Fig._ 3.) From another
leaf he removed the inferior portion of the intumescence: he found,
upon _this_ injury, that the leaf declined more than before, and
did not again rise, (_Fig._ 4.) He noticed that a thin slice, pared
from either surface of the intumescence, has a like effect, but in
a less degree than a deep excision: and he found that when similar
experiments are made upon the intumescence of the subpetiole, there
is no essential difference in the result.

Thus Mr. Lindsay discovered, that the force which raises the petiole
exists in the lower part of the intumescence, and that which
depresses it, in the upper. He seems to have considered that the
temporary excess of force in either part is produced by an impulsion
of the sap from the vessels of the yielding portion into those of the
opposite portion. [p080]

Dr. Dutrochet viewed these phenomena in some respects more justly. He
remarked, in addition to what Lindsay had observed, that if, instead
of the upper and under surface, the lateral part of the intumescence
be removed, the petiole becomes not raised or deflected, but inclined
towards the side on which it is injured (_Fig._ 5); and that if
longitudinal slices of the upper, or under, or lateral portions
of the intumescence are immersed in water, these separate slices
immediately become incurvated, that edge being concave which looks
towards the axis of the intumescence. From these facts Dutrochet
inferred that the texture of the intumescence possesses some
modification of irritability; that, when excited, each length of the
intumescence (to use a very imperfect expression) forcibly assumes
an incurvated figure, like a curved spring returning from a state of
temporary extension; that the petiole is raised, when the action of
the lower part of the intumescence predominates; is depressed, when
the upper portion acts with increased energy.

Mr. Burnett and myself had arrived at very similar conclusions
respecting the agency of the intumescence, before we became
acquainted with the inquiries of Lindsay and Dutrochet.

In Dutrochet’s able researches, a more exact analysis, however,
was obtained of the functions of this part. He discovered that the
cortex of the intumescence is the seat of its irritability: for upon
wholly removing the bark, so as to expose the ligneous substance, the
petiole was found to have been rendered motionless. Nevertheless,
the intumescence, thus mutilated, remains capable of transmitting an
impression made upon its leaflets to the leaves adjoining, Dutrochet
further ascertained, that the ligneous substance alone is fitted to
convey the peculiar stimulus, which spreads, from a point of the
plant that has been irritated, to the adjoining leaves.

The experiments already mentioned appear to explain the mode in which
the elevation and depression of the petiole, and the divergence
and approximation of the subpetioles are produced. It is probable
that the contrivance for folding and expanding the subleaflets is
of a similar nature. Mr. Burnett and myself conjectured that each
subleaflet is raised by the under part of the intumescence that
exists at its base, and [p081] depressed by some action of the upper
portion of the same intumescence. In trying the soundness of this
hypothesis, we met with the following evidence in its favour:—

Mr. Lindsay had observed, that at the moment when the petiole is
depressed, the under part of its intumescence assumes a deeper
colour. But the under part of the intumescence of the petiole is
the portion which is shortened during its depression, and which is
overcome on this occasion by the superior force of the upper portion.

Now it is to be remarked that in the subleaflets the upper part
of the little intumescence belonging to each corresponds, in one
respect alluded to, with the lower portion of the intumescence of
the petiole; _it is the portion shortened when the leaf is folded_.
And we found, upon examination, that it likewise distinctly changes
colour at the moment when the subleaflet rises, while the under
surface of the intumescence of the subleaflet does not change its hue.

In pursuing this inquiry, another point of correspondence between
the mechanism which depresses the petiole, and that which raises the
subleaflets, was stated, which has yet additional interest.

 [Illustration: _Fig._ 6.]

 [Illustration: _Fig._ 7.]

 [Illustration: _Fig._ 8.]

When the plant is not in its most lively state, the under surface of
the intumescence of the subleaflet (_b_, _Fig._ 2,) and the upper
surface of the intumescence of the petiole (_a_, _Fig._ 6,) may be
pricked with a needle, without producing action. But if the opposite
surfaces, those namely, which change colour and are shortened when
the petiole is depressed and the subleaflets folded, are touched
with the point of the needle these actions are instantaneously
produced. Here the [p082] subleaflet is most delicately sensible;
_a slight touch_ with the point of a needle upon the upper surface
of the intumescence of the subleaflet (_c_, _Fig._ 1,) causes the
single subleaflet so stimulated to rise; and in this manner all the
subleaflets upon one side of a leaflet may be raised, their fellows
remaining expanded: if the touch be something sharper, the fellow
subleaflet rises at the same time; if ruder still, the next pair of
leaflets fold directly afterwards, and the irritation then proceeds
entirely through the leaflet. But the most satisfactory and curious
results are obtained on stimulating the extension surface of the
intumescence of the petiole. The needle may be applied to every point
upon the upper or solar half of the intumescence of the petiole
(_a_, _Fig._ 6,) without producing any visible effect; but if the
irritation be applied upon the under half, (_d_, _Fig._ 6,) either
quite below or laterally, the petiole is immediately depressed. The
transition is abrupt from the surface against which the needle may be
made to prick, without exciting action, to one which, when the needle
reaches it, causes the petiole to be instantaneously thrown down.

It appears, therefore, that each intumescence has a surface
especially adapted to receive mechanical impressions; which surface
is placed on the side of the intumescence opposite to that, by which
the consequent motion is produced. A curious but vague analogy may be
traced between these surfaces of the sensitive plant and the organs
of sense in animals.

We painted with a thick layer of lamp-black in oil the intumescence
of different petioles in different ways; the upper surface of one,
the under surface of another, the side of a third. The experiment was
followed by no sensible effect. After a few minutes the petioles,
which had been thrown down by the operation, rose again in each case,
and fell again as readily as before upon being stimulated afresh.

We tried what result would ensue upon slitting the intumescence of
the petiole horizontally. The petiole, after this injury, did not
recover its usual direction; the intumescence appeared to have wholly
lost its properties; the leaf seemed to depress the petiole by its
weight alone, yet the leaflets expanded, and exhibited their usual
irritability, upon the depending stalk. The same effect, however, was
observed, when the [p083] intumescence was divided by a longitudinal
incision, made vertically instead of horizontally.

I have already mentioned that Dutrochet discovered that the ligneous
fibre is the channel, along which an impression is conveyed from
one part to another. Mr. Burnett and myself had made one or two
experiments upon the course which the irritation follows when
spreading from leaflet to leaflet, where several are placed upon the
same petiole.

If the upper third of a petiole bearing four leaflets be divided
longitudinally, the irritability of the leaflets remains for many
days unimpaired; upon cutting with scissors one subleaflet after the
plant has recovered itself, the irritation is observed to descend
the wounded leaflet, and then to pass to that adjoining upon the
same side of the petiole: afterwards the petiole falls, but there
the effect stops; it does not extend to the two other leaflets;
the direct route is cut through, and the irritation seems to find
no circuitous way, as might have been expected, perhaps through
the intumescence of the petiole back again to the leaflets, on its
summit. If on a petiole, bearing four leaflets, a lateral incision be
made, cutting the petiole half through it at a point between the two
leaflets which are situated on one side, upon irritating either of
the leaflets, between which the incision has been made, it folds its
subleaflets; then the two opposite leaflets fold _their_ subleaflets;
and _last of all_, the leaflet next adjoining that first irritated,
but isolated from it by the incision, becomes folded.

In the few remarks which I have thus put together, I have quoted
Lindsay and Dutrochet only as far as their researches anticipated
my own: I leave unnoticed many experiments, in several of which
these authors are again found to have accidentally coincided. The
experiments to which I allude do not, however, serve to illustrate
the nature of the motion exhibited by the sensitive plant, to the
examination of which subject alone my attention was, in the present
instance, directed, in the expectation that it might throw light upon
the obscure and interesting subject of muscular action.

 I remain, my dear Sir, Your’s truly,
 HERBERT MAYO.

 19, _George Street, Hanover Square_,
 _August 29, 1827_.

[p084]




 _Experiments on the Nature of Labarraque’s disinfecting Soda
 Liquid_. By M. Faraday, F.R.S., Corr. Mem. R. Acad. Sciences, Paris,
 &c. &c.


1. The following experimental investigations relate to the nature of
that medicinal preparation which M. Labarraque has lately introduced
to the world, and named _Chloride of oxide of Sodium_. They were
occasioned by the accounts which were given of this and other
substances of similar power, to the members of the Royal Institution,
at two of their Friday evening meetings[31]; the value of the
preparation, the uncertainty of its nature, and the inaccuracy of its
name, all urging the inquiry.

2. In the first instance the inquiry was directed to the nature of
the action exerted by chlorine gas upon a solution of carbonate
of soda, questions having arisen in the minds of many, whether it
was or was not identical with the action exerted by the same gas
on a solution of the caustic alkali, and whether carbonic acid was
evolved during the operation or not. Chlorine gas was therefore
carefully prepared, and after being washed was sent into a solution
of carbonate of soda, in the proportions directed by M. Labarraque;
_i. e._ 2800 grains of crystallized carbonate of soda were dissolved
in 1.28 pints of water; and being put into a Woulfe’s apparatus,
two-thirds of the chlorine evolved from a mixture of 967 grains
of salt with 750 grains of oxide of manganese, when acted upon by
967 grains of oil of vitriol, previously diluted with 750 grains
of water, were passed into it; the remaining third being partly
dissolved in the washing water, and partly retained in the open space
of the retort and washing vessel. The operation was conducted slowly,
that as little muriatic acid as possible might be carried over into
the alkali. The common air ejected from the bottle containing the
solution was collected and examined; but from the beginning to the
end of the operation not a particle of carbonic acid was disengaged
from the solution, although the chlorine was readily absorbed.
Ultimately a liquid of a very pale [p085] yellow colour was obtained,
being the same as M. Labarraque’s soda liquor, and with which the
investigations were made that will hereafter be described.

3. An experiment was then instituted, in which the effect of excess
of chlorine, upon a solution of carbonate of soda of the same
strength as the former, was rendered evident. The solution was put
into two Woulfe’s bottles, the chlorine well washed and passed
through, until ultimately it bubbled through both portions without
absorption of any appreciable quantity. As soon as the common air
was expelled, the absorption of the chlorine was so complete in the
first bottle, that no air or gas of any kind passed into the second,
a proof that carbonic acid was not liberated in that stage of the
experiment. Continuing the introduction of the chlorine, the solution
in the first bottle gradually became yellow, the gas not being yet
visible by its colour in the atmosphere above the solution, although
chlorine could be detected there by litmus paper. Up to this time no
carbonic acid gas had been evolved; but the first alkaline solution
soon acquired a brighter colour, and now carbonic acid gas began
to separate from all parts of it, and passing over into the second
bottle, carried a little chlorine with it. The soda solution in the
first bottle still continued to absorb chlorine, whilst the evolution
of carbonic acid increased, and the colour became heightened.
After some time the evolution of carbonic acid diminished, smaller
quantities of the chlorine were absorbed by the solution, and the
rest passing into the atmosphere in the bottle, went from thence
into the second vessel, and there caused the same series of changes
and actions that had occurred in the first. The solution in the
first bottle was now of a bright chlorine yellow colour, and the gas
bubbled up through it as it would through saturated water.

4. When the chlorine had saturated the soda solution in the second
bottle, and an excess of gas sufficient to fill several large
jars had been passed through the whole apparatus, the latter was
dismounted, the solutions put into bottles and distinguished as
the saturated solutions of carbonated soda; they were of a bright
greenish-yellow colour, and had an insupportable odour of chlorine.

5. The saturated solution (4) was then examined as to the [p086]
change which had been occasioned by the action of the chlorine. It
bleached powerfully, and apparently contained no carbonated alkali:
but when a glass rod was dipped into it and dried in a warm current
of air, the saline matter left, when applied to moistened turmeric
paper, reddened it considerably at first, and then bleached it; and
this piece of paper being dried and afterwards moistened upon the
bleached part, gave indications of alkali to fresh turmeric paper.

6. A portion of the saturated solution (4) being warmed, instantly
evolved chlorine gas, then assumed a dingy appearance, and ultimately
became nearly colourless; after which it had an astringent and saline
taste. Being evaporated to dryness at a very moderate temperature, it
left a saline mass, consisting of much common salt, a considerable
quantity of chlorate of soda, and a trace of carbonate of soda. This
mixture had no bleaching powers. The dingy appearance, assumed in
the first instance, was found to be occasioned by a little manganese
which had passed over into the solutions, notwithstanding the care
taken in evolving and washing the gas.

7. From these experiments it was evident that when chlorine was
passed _in excess_ into a solution of carbonate of soda (3), the
carbonic acid was expelled, and the soda acted upon as if it were
caustic, a mixture of chloride of sodium and chlorate of soda being
produced; with the exception of the small portion of carbonate of
soda which, it appears, may remain for some time in the solution in
contact with the excess of chlorine at common temperatures, without
undergoing this change. The quantities of chloride of sodium and
chlorate of soda were not ascertained, no doubt being entertained
that they were in the well-known proportions which occur when caustic
soda is used.

8. The Labarraque’s soda liquor which had been prepared as described
(2), was now examined relative to the part the chlorine played in
it, or the change the alkali had undergone, and was soon found to
be very different to that which has been described, as indeed the
experiments I had seen made by Mr. Phillips[32] led me to expect. The
solution had but little odour of chlorine, its taste was at first
sharp, saline, scarcely at [p087] all alkaline, but with a persisting
astringent biting effect upon the tongue. When applied to turmeric
paper, it first reddened and then bleached it.

9. A portion of the solution (2) being boiled, gave out no chlorine;
it seemed but little changed by the operation, having the same
peculiar taste, and nearly the same bleaching power as before. This
is a sufficient proof that the chlorine, though in a state ready to
bleach or disinfect, must not be considered as in the ordinary state
of solution, either in water or a saline fluid; for ebullition will
freely carry off the chlorine under the latter circumstances.

10. A portion evaporated on the sandbath rather hastily, gave a dry
saline mass, quite unlike that left by the _saturated solution_
already described (6); and which, when dissolved, had the same
astringent taste as before, and bleached solution of indigo very
powerfully: when compared with an equal portion of the unevaporated
solution, which had been placed in the mean time in the dark, its
bleaching power upon diluted sulphate of indigo was 30, that of the
former being 76. Another portion, evaporated in a still more careful
manner, gave a mass of damp crystals, which, when dissolved, had the
taste, smell, and bleaching power of the original solution, with
almost equal strength.

11. These experiments shewed sufficiently that the whole of the
chlorine had not acted upon the carbonate of soda to produce chloride
of sodium, and chlorate of soda; that much was in a peculiar state of
solution or union which enabled it to withstand ebullition, and yet
to act freely as a bleaching or disinfecting agent; and that probably
little or none had combined with the sodium, or been converted into
chloric acid. To put these ideas to the test, two equal portions of
the Labarraque solution were taken; one was put into a large tube,
closed at one extremity, diluted sulphuric acid was added till in
excess, and then air blown through the mixture by a long small open
tube, proceeding from the mouth, for the purpose of carrying off
the chlorine; the contents of the tube were then heated nearly to
the boiling point, air being continually passed through. In this
way all the chlorine which had combined with the carbonated alkali
without decomposing it, was set free by the sulphuric acid, and
carried off by the current of air and vapour, whilst any which had
acted chemically upon the alkali would, [p088] after the action of
the sulphuric acid, be contained in solution as muriatic and chloric
acids, 

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