Outlines of Creation
by Elisha Noyce · English · Gutenberg #48876 · 521,687 chars · public domain (US)
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Title: Outlines of Creation
Author: Elisha Noyce
Release date: May 4, 2015 [eBook #48876]
Most recently updated: October 24, 2024
Language: English
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*** START OF THE PROJECT GUTENBERG EBOOK OUTLINES OF CREATION ***
[Illustration: Showing the five groups considered in the book]
[Illustration: Group of Extinct Animals.]
OUTLINES
OF
CREATION.
BY
ELISHA NOYCE.
AUTHOR OF
"THE BOY'S BOOK OF INDUSTRIAL INFORMATION."
ILLUSTRATED WITH
FOUR HUNDRED ENGRAVINGS,
BY
THE BROTHERS DALZIEL.
LONDON:
WARD & LOCK, 158, FLEET STREET.
1858.
(_The right of Translation is reserved._)
Dalziel, Brothers, Camden Press, London.
CONTENTS.
THE SKY.
PAGE
Sky, definition of 1
Stars, what they are 1
Sun, probable planets of 2
Nebulæ 2
Solar system 3
Planets, list of 3
Sun, the source of light 3
" size, diameter, &c. 3
" spots on 3
" compared with size of planets 4
Orbits, elliptical 5
Ellipse, definition of 5
Earth's orbit, form of 6
Mercury 6
Venus 7
Planets, inferior and superior 7
" conjunction and opposition of 8
The Earth 8
" form of, demonstrated 9
" diurnal motion of 10
" rate of motion of 10
Equinoxes and solstices 12
The Moon 12
" phases of 13
Mars 14
Jupiter 16
" satellites of 18
Saturn 18
" rings of 19
Uranus 21
Neptune 22
The planetoids 22
" supposed origin of 23
The stellar system 24
Stars, number of 24
The Milky Way 24
Nebulæ 24
Constellations 25
Stars, double 26
" variable 27
Comets 27
THE AIR.
Air, how perceived 29
" composition of 29
" weight of 30
Barometer, principle of 30
Winds, course of 31
Vapour, condensation of 31
Snow, hail, and frost 32
" red and green 32
Air, temperature of 32
Dew, cause of 33
" artificial formation of 34
Clouds and fogs 35
Lightning 36
" conductors 37
Thunder-storms 38
Rainbow 39
Air, the source of nourishment 40
" carbonic acid of 41
" the source of coal 41
THE EARTH.
Elements, list of 45
Earths, list of 46
Silica 46
Alumina, Lime, Potassa 47
Soda 48
The Earth, surface of 49
Strata 49
" diagram of 50
" various positions of 51
Faults or dykes 52
Granite 53
Gneiss 54
Strata, primary 54
Earth, primary period of 55
Stalagmites, formation of 58
Terebratula 58
Secondary system 59
Trilobites 59
Mountains, formation of 61
Earth, section of part of 62
Volcanoes, formation of 62
Coral polypi 64
Encrinites 65
Mountain limestone 65
Basalt 66
Tree-ferns, Pines, &c. 66
Air, purification of 67
Coal, formation of 67
" consumption of 68
Coal shales, ferns found in 69
Earth's surface, alterations of 69
Labyrinthodon 70
Red Sandstone, impressions in 70
Saliferous system 71
Lias and oolite 71
Ammonites and pentacrinites 72
Cretaceous system (chalk) 72
Ichthyosaurus and plesiosaurus 73
Coprolites 74
Chalk, organic remains in 75
" flints of 76
Strata, tertiary 78
Alluvium and diluvium 78
" quadrupeds of 78
Dinotherium 79
Mammoth, &c. 80
Irish elk, paleotherium 81
Boulder formation 82
Fossil leaves 83
Man, as yet unformed 83
" his remains only in upper strata 83
Sculptures from Nineveh 84
Earth's surface, always changing 84
" as it is 86
Earth, temperature of 86
Europe 87
Asia and Africa 88
America 88
Australia 89
The Great Desert 89
Oceans 90
THE WATERS.
The waters 91
Sea-weeds, &c. 92
The horizon 93
The cliffs 93
The waters, their divisions 93
The sea, always the same level 94
" waters poured into it 94
Rain, how produced 95
Rivers and streams 96
" causes of their overflowing 97
Lakes 97
Chalk downs, &c., once a sea bottom 98
Sea, its encroachments 98
" waves of 99
" Sargasso 101
Gulf stream 101
Sand, formation of 102
" none in deep seas 102
Diatomaceæ 103
Foraminiferæ 104
Salt, the source of 104
Sea-water, composition of 105
Tides 105
Waters, beneficially arranged 107
Steam navigation 108
Introduction to organic kingdoms 110
THE VEGETABLE KINGDOM.
Quantity, distribution, &c. 112
Forests of Russia and America 113
Sargasso sea, sea-weed 114
Diatomaceæ 114
Fungi, mould, mildew, &c. 116
Coral reef, fertilisation of 118
Vegetables, composition of 118
" feed on the air 119
" the food of animals 119
" mode of growth 120
" action of light and heat on 121
Seeds, germination of 122
Growth, promoted by rain 123
Endosmose, experiment on 123
Carbonic acid decomposed by
plants 124
Sap, course of 124
Vegetables, position they hold 125
" compared with radiata 126
" description of parts of 127
Leaves, forms of 130
Corolla, forms of 132
Stamens, arrangement of 133
Fruit, forms of 134
Inflorescence, forms of 136
Vegetable kingdom, divisions of 139
Acrogenæ 141
Algæ 141
Fungi 143
Lichens, ferns 144
Liverworts 145
Mosses, various 146
Horsetails 147
Endogenæ 147
Bamboo, applications of 152
Endogenæ, orders of 154
Grasses 154
Sedges, Arums 155
Bull-rush, Colchicum 156
Lily, Narcissus 157
Crocus, Orchids 158
Naiads, Flowering rushes 159
Water Plantain 160
Exogens 160
" wood of 161
" age of 162
Baobab 163
Woods, various kinds of 165
Galls, formation of 167
Wood, uses of 167
Exogens, size of 168
Wellingtonia Gigantea 168
Banyan 170
Exogens, sub-classes of 170
Thalamifloræ, orders of 171
White Water Lily 171
Poppies, Monkshood 172
Fumitory, Water-cress 173
Helianthemum, Berberry 174
Violet, Sun-dew 175
Milkwort, Bachelor's Buttons 176
Lime Tree, St. John's Wort 177
Marsh Mallow, Meadow Geranium 178
Flax, Maple Tree 179
Rue, Wood Sorrel 180
Calycifloræ, orders of 181
Spindle Tree, Buckthorn 181
Broom, Garden Pea 182
Pear Tree, Rose, Strawberry, Loose Strife 183
French Willow, Myrtle 184
House-leek, Gooseberry 185
London Pride, Fennel, Hemlock 186
Corollifloræ, orders of 187
Melon, Dogwood 187
Honeysuckle, Guelder Rose, Cross Wort 188
Valerian, Red Valerian, Teasel 189
Coltsfoot, Ox-eye Daisy, Harebell 190
Grey Heath, Gentian, Buck-bean 191
Pimpernel, Primrose, Bindweed 192
Borage, Sage 193
Tobacco 194
Speedwell 195
Butterwort, Plantain 196
Thrift, Holly 197
Monochlamydeæ, orders of 197
Ladies' Mantle 197
Beetroot, Buckwheat 198
Oleaster, Spurge Laurel 199
Sweet Chestnut, Box 200
Hop, White Willow 201
Birch, Alder, Elm 202
Larch, Yew, Bay 203
Plants, list of poisonous 204
Monk's-hood, Wolf's-bane 204
Bryony, Green Hellebore, Stinking Hellebore 205
Mezerium, Meadow Saffron 206
Foxglove, Staves-acre 207
Nightshade 208
Hemlock, Thorn Apple 209
Poppies, Henbane 210
Caper, Wild Lettuce 211
Fungi, poisonous 212
THE ANIMAL KINGDOM.
Animalculæ in water 215
Man, created, not developed 217
Animals, chief division of 217
Animals, invertebrate 217
Infusoria 218
Protozoa 218
Infusoria, higher kinds of 220
Entozoa (intestinal worms) 221
Zoophytes (Sertularia, &c.) 221
Sponge 222
Gorgonia 222
Actinia 223
Corals (Tubipora musica, &c.) 224
Flustra (Sea mats) 225
Echinodermata (Star-fishes, &c.) 225
Sea urchins, &c. 226
Articulata 227
Annellata (Worms, &c.) 227
Cirripeda (Sea acorns) 228
Crustacea 229
Insects 231
" metamorphoses of 231
" parts of 232
" depredations by 234
" orders of 236
Beetles 236
Grasshoppers, Locusts, &c. 237
Dragon-flies, May-flies, &c. 238
Bees, Wasps, &c. 240
Ants, habitations of 240
White Ants 245
Stylops 247
Butterflies, Moths, &c. 248
Silkworm 249
Bugs, Aphides, &c. 250
House-fly, Gnat, &c. 250
Flea, Chigoe 251
Spiders and Scorpions 252
Mollusca 252
Nautilus, mussel, &c. 255
Tunicated molluscs 255
Lingula, Terebratula, &c. 256
Oyster, cockle, scallop, &c. 256
Clio borealis 257
Snail, slug, whelk, &c. 257
Cuttle-fish, nautilus, &c. 258
Vertebrata 259
Fishes, description of 259
Fishes, divisions of 260
Perch, Mackerel, Gurnard, &c. 261
Salmon, Pilchard, Pike, &c. 262
Turbot, Plaice, Soles, &c. 265
Eels 266
Pipe-fish, Sea Horse 267
Sea Porcupine, Sun-fish 268
Sturgeons, Sharks 269
Lamprey 270
Reptiles 271
Frogs and Toads 271
Snakes 272
Lizards, Crocodiles, &c. 274
Turtles and Tortoises 276
Birds 279
" divisions of 280
Eagles, Falcons, &c. 281
King-fisher, Woodpecker, &c. 281
Poultry, Pheasants, &c. 282
Herons, Cranes, &c. 284
Swans, Geese, &c. 285
Mammalia, orders of 286
Kangaroo, Opossum, &c. 287
Duckbill 288
Rat, Beaver, Hare, &c. 289
Anteaters 291
Ox, Deer, &c. 292
Horse, Elephant, Hog, &c. 294
Whale, Narwal, &c. 296
Lion, Tiger, &c. 297
Dogs, Wolves and Jackalls 302
Bears 302
Seals and Walrus 303
Mole, Hedgehog, &c. 303
Bats 304
Monkeys 305
Man 307
Man the only possessor of reason 308
Skeleton, diagram of 309
" parts of 310
Bones, description of 311
Muscles 312
" voluntary and involuntary 313
Ligaments and cartilages 313
Form, affected by age and sex 314
" in infancy 315
" in middle age 315
" in old age 316
" affected by sex 316
Senses, special 317
Sight 317
Eye, structure of 319
Eyes, compound 320
Hearing, smell, taste 321
Touch 322
Digestion 322
Respiration 325
Circulation of Blood 326
Man, his superior faculties 327
" varieties of 328
European race 328
Basks 329
Skiptar, Kelts (or Celts), Greeks and Latins, Sarmatians,
Germans 330
Abyssinians 331
Mongolians 332
Hottentots 333
Malays 334
Papuans, Negrillo 335
Indians, or Telingans, Ethiopians 336
Australians, Negro 337
Races, numerical table of 338
INTRODUCTION.
The object of this work is to bring before the reader a simple and
intelligible description of the whole Creation, without attempting
to enter into minute particulars on any of the subjects more than
is sufficient to present them in a form clear enough to be both
comprehended, and recollected; thus aiming at the production of a
taste for such knowledge, and a desire to enter more minutely into any
or all of the subjects this work embraces, which desire can easily
be gratified by a study of some of the many excellent works devoted
exclusively to the individual parts, which in this work are treated
of collectively. The want of a general knowledge of those works of
the Great Creator which are constantly spread out before us, in these
days of easy acquirement, amounts almost to a sin, for it is by the
study of Nature in all her varied forms and associations, that we learn
to "look from Nature up to Nature's God;" for who can look upon the
works of God without a feeling of awe and admiration? who can look
upwards at "the spacious firmament on high," without a sense of his
own insignificance? who can gaze around upon the beauty and variety
the earth displays, without a strong desire to know more of such a
Great Creator's works?--and he who knows the most, be sure it is he
who will worship Him with the truest and most heartfelt gratitude and
admiration. The works of God (next to the Divine revelation of His
will) are the highest studies to which Man can apply his intellect; it
has required the greatest study of the greatest minds to find out and
record but a few facts to add to the general store, and surely no one
should consider his time misspent who can read over such records, and
trace their truth by comparison with Nature, the more especially as it
is by these means a love of inquiry is engendered, and that ultimately
he may be enabled by diligent perusal of the great Book of Nature, to
add his quota to the store of knowledge already formed and recorded.
It is true that infidels have often brought forward some branch of
Science in confutation of Scripture, but it is also a fact that in
nearly every such case, the very arguments that have been used by these
men, have at last become the strongest arguments on the other side.
Geology was at first adduced as a proof that the world had existed
from all eternity, instead of having been created by an Omnipotent
God, and the question had often been asked, "Can you produce one proof
of the creation of anything?" Now this was a difficult question to
answer, until Geology made manifest the fact that Man was created, by
producing a clear and unimpeachable proof that up to a certain time, he
did _not_ exist on the earth, and that at a period of time, a little
later, he _did_ exist; the space between these epochs is not known,
but it has nothing to do with the argument, for within that period
(whatever it may have been) Man _was_ created, and created as perfect
in his physical organisation as he is at present--no long series of
developments from the higher animals by fortuitous circumstances, as
some pretend--no gradual addition of parts to suit the physical changes
of the earth's surface. There is undoubted proof from the oldest
records, in the form of Sculptures, that Man's appearance has always
been the same, and the records of the Bible (the _antiquity_ of which,
at all events, cannot be disputed) show that the constitution of his
mind was at that time just as it is now--every passion, every desire
the same--the only advance he has made, is in the knowledge of God's
works; the application of that knowledge to his own benefit, and the
glorification of his Maker.
THE SKY.
[Illustration: FIG. 11. TELESCOPIC APPEARANCE OF THE MOON.]
The Sky is the familiar name used to express that wonderful and vast
expanse of space which extends on all sides far beyond our knowledge
or conception, and in which the earth and millions of other orbs move
round suns as their centres. Countless millions of these suns exist
at immense distances apart and of the most prodigious magnitudes
(many thousand times larger than this earth), these are the stars
which on clear nights we see twinkling so brightly in the sky; our
sun is one of them, but being very much nearer to us than the others
it appears proportionately larger and brighter, and is our centre of
attraction and circulation. There is but little doubt that every star
has its circulating worlds or "planets," but these are too small to
be seen even with the best telescopes; this may be understood when it
is considered that the stars themselves, by the most powerful aids,
appear but as bright points or specks, and they are thousands of times
larger than the worlds which would circulate round them. But though
their planets cannot be perceived by the naked eye, yet analogy teaches
us that they in all probability exist, for very many of the heavenly
bodies have satellites revolving round them, of such are our moon and
the moons of Jupiter, and in this sense the planets themselves may
be considered as the satellites of the sun, and as the sun has its
satellites revolving round it, it is fair to conclude that it is not
the only one of all the stars which has. All these thousands of suns
and planets, millions of miles apart, and occupying space, the extent
of which we have no terms to express, form but one system of stars out
of many, for by comparison with infinite space they occupy but a point,
telescopes of the greatest power having revealed that beyond all these
stars, there is an immense space in which are seen other systems of
stars, as great and numerous as our own, to which the name "Nebulæ"
has been given. The mind fails to reach to such magnitude, and it is
certain that the study of these great things, brings us to regard
size and space (like time) as nothing; for it appears that God has
expanded or contracted His works at will to suit His plan of creation
without regard to limit; whether we look at the most minute shell or
the greatest orb, still His marks of design are equally evident. If we
consider it wonderful that God should take up hundreds of millions of
miles for one system, and that He should scatter through space millions
of such systems, then let us lay aside the telescope and, after an
exclamation of adoration, take up the microscope, by which we shall
learn that God has also placed millions of systems equally wonderful
within the compass of an inch! We shall at once acknowledge that he
is "Lord of all," and that size, space, quantity, and time, are mere
fictions of our own imperfect minds, and that to an Infinite God there
is no difficulty from such sources.
THE SOLAR SYSTEM.
This is the name given to that collection of worlds which, with the sun
as a centre, circulate at different distances from and around it. There
have at present been discovered eight large planets and thirty-four
smaller ones called "asteroids" or "planetoids," the larger planets
revolving in the following order from the sun or centre:--
1. MERCURY.
2. VENUS.
3. THE EARTH.
4. MARS.
5. JUPITER.
6. SATURN.
7. URANUS.
8. NEPTUNE.
The Sun, the centre of the solar system, is the great source of light
and heat to our planet and all others which revolve around it, as well
as of another agent not so well understood, namely "actinism," or that
power which produces the chemical changes in many substances exposed to
the sun's rays, and which has been of late turned to such useful and
wonderful account in the art of photography.
The sun is an immense sphere, many thousand times larger than our
earth, or indeed all the planets put together. It turns upon its axis
in twenty-five days, and, like all spheres which rotate, has a slightly
flattened form; it is supposed that the sun itself, carrying its
planets with it, performs a journey round some other centre very far
away, but for all the purposes of explaining the solar system it may
be supposed to be stationary. The diameter of the sun is about 890,000
miles, or nearly 112 times the diameter of our earth, and as the bulk
of spheres is as the cubes of their diameters, it follows that the
sun is about 1,400,000 times the bulk of the earth. Fig. 1 shows the
relative size of the sun and the planets which rotate round it; the
specific gravity of the sun is about a quarter that of our earth or
one-and-a-half times that of water. On its surface irregularities are
seen (by the aid of the telescope) which give it a wavy appearance,
and beside these, black spots or tracts (_maculæ_) which appear to
traverse from west to east, across its face; these however do not
travel on, but are carried round by the sun in its rotation, for
by observing any one of them, it is seen to go across and make its
appearance again at the other side, and the time it takes to arrive at
the place where it was first seen, determines the time of the sun's
rotation, which (as before stated) is twenty-five days or nearly; these
spots alter in size, form, and number from time to time, some of them
remaining permanent for months, others closing in and disappearing in a
few hours.
[Illustration: FIG. 1. PLANETS COMPARED WITH A QUARTER OF THE SUN.]
These black spots have a sort of shadowy fringe (_penumbra_) which
gives them the appearance of being openings through a luminous surface,
discovering a surface less luminous, with openings in it through which
some still darker surface is seen; that this really is the case, and
that these are not merely dark spots or surfaces, is shown by the
fore-shortening of the nearest edge as they arrive at the verge of the
sun's disc, and are consequently presented edgewise to the eye, so that
a spot may have the appearance of fig. 2 when seen in front-view near
the centre, and of fig. 3 when seen fore-shortened near the edge of the
sun's disc. These spots (although but specks in comparison with the
vast surface of the sun) are yet of prodigious magnitude, some having
been calculated to measure 18,000 miles across--large enough for two
such worlds as ours to pass through side by side! From the rapid motion
of the "penumbra" or edges of these spots, which alter, open, and
close up very rapidly, and from some of them being semi-dark, others
quite dark, &c., it has been concluded that the sun has at least two
surrounding atmospheres, that the body of the sun is not luminous, nor
the first atmosphere or that nearest to it, but that the outer one is,
and that the dusky appearance of the inner, as seen through openings
of the luminous outer atmosphere, results from its being very strongly
illuminated by the outer one; this luminosity may be (and probably is)
only comparative, for the spots which appear black may be yet very
bright, appearing black only in comparison with the extreme brilliancy
of the outer atmosphere, just as a bar of red-hot iron appears black
when held up to the sun. The course which the planets take round the
sun is not exactly circular, but deviating from it more or less, never
being quite a circle. The orbit of each planet, if accurately computed
and laid down on paper, proves to be that form of curved line called
an "ellipse," or that form which instead of having one centre, as in
the circle, from which all lines radiating to the circumference are
equal in length, has a longer and shorter diameter, two centres called
"foci," and the circumference or boundary so placed that the sum of
any two lines, drawn one from each centre, and meeting at any part of
the circumference, shall be equal to any two other lines so drawn and
meeting at any other point of the circumference, and to the major axis
or long diameter of the ellipse. In fig. 4, each pair of lines drawn
from A A and meeting repectively at B are each equal.
An ellipse may be very much elongated, or almost circular, but still
have these properties which are essential to it, and in the case of the
orbits of the planets, they are so nearly circular, that if drawn a few
inches wide, would hardly be detected to differ from the circle. The
orbit of the earth is about one thirtieth part longer than broad.
[Illustration: FIG. 2.]
[Illustration: FIG. 3.]
[Illustration: FIG. 4.]
The rate at which the planets revolve round the sun is not equable,
that is, their progress is not through equal distances at equal times,
but a line drawn from the planet to the sun would always pass over
equal spaces or "areas" in equal times, for example, in fig. 5, if the
area of the angle included in A B C be equal to that included in A D E,
then a planet would pass from B to C and from D to E in equal times.
Mercury is the smallest of the greater planets, and the nearest to the
sun. Its diameter is about 3000 miles, and it is about one-fifteenth
part the volume of the earth; its distance from the sun is 36,770,000
miles, and it performs its revolution in eighty-eight days.
[Illustration: FIG. 5.]
This planet is but seldom seen with the naked eye; for, being so
(comparatively) near to the sun, it sets before dark, and does not rise
till the grey of morning makes it scarcely visible. Nothing notable has
been discovered on its surface.
Venus is the second in rotation from the sun, and revolves round it,
at a distance of 68,750,000 miles, in 224-1/2 days. The diameter of
Venus is about 7760 miles, it is therefore nearly the volume of the
earth. This is the brightest planet seen in the heavens, for although
much smaller than many others, its comparative nearness to the sun
and earth causes it to appear larger and brighter to the eye. Venus
is the evening and morning star; for when to the west of the sun, it
rises before it, and is then called "the morning star" (or, formerly,
"Lucifer"), but when it is to the east of the sun, it sets after
twilight is gone, and is called "the evening star," or "Hesperus."
These two planets, Mercury and Venus, have "phases" (like the moon),
or certain positions in which the whole of the side illuminated by the
sun is seen from the earth, and other positions in which it is seen
sideways; the planet is then said to be in "quadrature," as may be seen
at Q Q, fig. 6. Mercury and Venus, being between the sun and the earth,
are called "inferior" planets, while those whose orbits are outside
that of the earth are called "superior" planets. When either of the
inferior planets are between the earth and the sun, they are said to
be in "inferior conjunction" (I C, fig. 6), and when on the
opposite side, or behind the sun, so that a straight line from it to
the earth would have to pass through the sun, then it is called being
in "superior conjunction" (S C); at mid-distance, either east
or west, it is said to be in "eastern" or "western quadrature."
[Illustration: FIG. 6. PLANETS SEEN IN QUADRATURE.]
The third planet from the sun is the Earth, distant about 95,000,000
miles, with a diameter of 7925 miles, so that the most lofty mountains
(five miles high) bear about the same proportion to it as would an
elevation one-fourteenth of an inch in height to a ball of ten feet in
diameter; therefore, with all its valleys and high hills, the surface
of the earth is smoother in proportion to its bulk than the rind of an
orange. The earth is not a perfect sphere, but has a slightly flattened
form, as though it had been compressed at the poles. The diameter at
the poles is the smallest, and is 7899 miles, while that at the equator
(its greatest) is 7925 miles, being a difference of twenty-six miles;
but this is so small, when compared with the size of the earth, that
if an exact model of it were made, four inches in diameter, it would
require the most accurate measurement to determine that it was not a
perfect sphere.
[Illustration: FIG. 7.]
The form of the earth has been demonstrated by accurate experiments and
calculations, but there are many things we may observe, convincing us
of its rotundity; one of the most evident of these is the fact that as
a ship at sea goes from the land, the hull first disappears, then the
lower sails, and lastly the tops, while a ship approaching the shore
shows first the topsails, and lastly the hull; see fig. 7, where A
shows a ship on the horizon, B hull-down, C out of sight. In the same
way, the tops of distant mountains are seen at sea long before the
lower lands. Another proof is drawn from the fact, that ships have been
sailed quite round the earth; by steering as nearly as possible in one
direction, they have arrived at the place from which they started.
A third proof of the earth's rotundity is found in the form of its
shadow, when the moon is eclipsed by it; this shadow, as thrown by the
earth upon the moon, is circular, in whatever position the earth may
be, and a sphere is the only solid form which can in all positions cast
a circular shadow.
The earth turns upon its axis every 23 hours, 56 minutes, and 4
seconds, which constitutes a day, and makes one revolution round the
sun in every 365-1/4 days, which make up a year; but the earth's axis
is not at a right angle to an imaginary line drawn from the earth to
the sun, but at an angle of 23 deg. 28 min. to it, as shown at fig. 8,
where the line from N to S is the earth's axis of rotation, the dotted
line leading to S is the sun's direction, and E Q is the equator.
[Illustration: FIG. 8.]
The earth travels through space at a rate of more than a
million-and-a-half miles per day, besides the distance which each
object upon it is carried in its diurnal rotation (24,000 miles). At
first thought it would seem impossible that such a rapid motion should
not be felt; but as the air and clouds, and every object belonging to
the earth, moves with it, and this motion is perfectly smooth, it can
only be perceived by looking at objects independent of the earth. If
sailing on the water, when it is quite smooth and the land not very
near, the ship seems to be stationary and the objects on shore appear
to pass along in an opposite direction to that in which the ship is
going. It is the same with the earth; the sun, which appears to move,
is stationary, while the earth is going round it; and the result is,
while the earth turns round on its axis the whole firmament appears
to move, we lose sight of those stars which are to the westward,
which are then said to "set," while those to the eastward, constantly
coming into sight, are said to "rise," the whole appearing to pass
from east to west, while in reality the earth's surface is passing
from west to east. At the equator, or that part of the earth which
lies midway between the poles, the sun and stars appear to rise and
set perpendicularly to the horizon and at equal times above and below
it, it is therefore 12 hours day and 12 hours night; in places not
situated on the equator, they do not rise and set perpendicularly to
the horizon, but form portions of circles at greater or less altitudes
in the heavens, and the nearer the observer is to either of the poles,
the smaller the circle, and the more of it is seen; so that, at the
poles, any star situated exactly overhead does not appear to move
at all. This place is called the north pole of the heavens, and the
nearest star to it is called the "polestar," which neither rises nor
sets, and, as it always keeps the same position, serves as a guide to
mariners. All this is the effect of the diurnal motion of the earth,
its annual motion not affecting the position of the stars, they being
at such an immense distance that the circle which the earth forms in
passing round the sun--although nearly 200,000,000 miles across--is as
a mere point in proportion. But not so with the sun: as before stated,
at the equator it is twelve hours above the horizon and the same time
below it; now, as we approach towards the poles, it forms at each
rotation an arc above the horizon, lower and lower, until at the poles
its daily rising and setting is lost altogether, and there would never
be daylight there, provided that the earth was only subject to the
diurnal motion (fig. 9); but as the earth turns upon an oblique axis,
the north and south poles share the blessing of daylight between them,
so that through one-half of the earth's orbit the north pole is towards
the sun, as shown in the figure, and the south pole during the other
half. There is therefore at the poles but one day and one night in
the year--the day being summer and the night winter. In less northern
climates, as England, this exists to a much smaller extent; for half
the year the sun is longer above than below the horizon, constituting
our summer, the other half of the year the sun is longer below the
horizon than above it, and this is winter. Hence, in each case, midway
between, the sun is twelve hours above and twelve below the horizon,
which occurs in spring and autumn, being called the "equinoxes" (equal
nights); the vernal or spring equinox takes place on the 21st of March,
the autumnal on the 21st of September. The times just between these,
when the sun is the longest and shortest time below the horizon, are
called the summer and winter solstices, and occur on the 21st of
December and the 21st of June.
[Illustration: FIG. 9.]
The earth has a smaller sphere or "satellite," circulating round
it, this is the Moon; it is placed at a distance of about 238,000
miles from the earth, is about one-fiftieth of its bulk or volume,
and revolves round it every 27-1/2 days, keeping always the same
side towards it, so that the other side has never been seen. This is
effected by rotation on its axis, which takes place once for every
circuit round the earth; if it did not rotate, or kept the same side
always to the same point of the heavens, then, when it had half-way
revolved, the other side would be turned towards the earth. There are
good reasons for believing that the moon has no atmosphere or air
around it, for the concave edge (when only a small portion of the half
illuminated by the sun is seen) instead of being gradually shaded off
into darkness, as would be the case if there were an atmosphere, is
well defined and uneven, showing the tops of some of the mountains and
their shadows (fig. 10). Nor does there appear to be any clouds, and as
a consequence no water; neither has anything been observed by the aid
of the best telescopes which could be considered sea, on the contrary,
the whole surface seems torn up and rent into chasms and immense
jagged mountains, enclosing circular portions like gigantic walls.
The darkened parts which are always seen on the surface of the moon
were formerly supposed to be seas, but of late, by the use of improved
instruments, they have been seen to be rough like the other parts, and
cannot therefore be water (fig. 11). As there appears to be no water,
it may be confidently inferred that there are no inhabitants.
[Illustration: FIG. 10.]
The moon having always one half illuminated by the sun, while the other
half is dark, presents different "phases" to us on the earth, according
to the position in which we view it; thus, in fig. 12, E represents the
central position of the earth, and S the direction from which the light
of the sun comes, the outer circle of moons represents the various real
positions of that luminary with respect to the earth and sun, and the
inner circle shows its appearance when in these various positions. When
the moon is between the earth and sun, as at _a_, it is said to be in
"conjunction," and as the darkened side is towards the earth, of course
it is not visible, this is "new moon" (a corruption of "no moon"); when
at _b b_, but a small part of the illuminated half is seen, and it is
then said to be "crescentic" (first and last quarter); at _c c_, half
of the bright side is seen, the moon is said to be at "quadrature," and
the appearance is that of a "half-moon;" at _d d_, the greater part of
the bright side is seen, and it is called "gibbous" and appears as a
"three-quarter-moon," and at _e_ the whole of the illuminated side is
seen; it is then "full-moon," and is said to be in "opposition."
[Illustration: FIG. 12.]
Beyond the earth the planet Mars (fig. 13) moves in its orbit round
the sun; it is the smallest, but one, of the larger planets, having
a diameter of but 4085 miles, and being only about one-seventh the
magnitude of the earth; it makes its revolution in 687 days, at a
distance of 144,780,000 miles from the sun.
[Illustration: FIG. 13.]
Owing to the brilliancy and proximity to the sun of Venus and Mercury,
together with other causes, no rotation has been observed in them, but
as this exists in all the other planets there is no doubt they also
rotate, but the nearness of Mars to the earth when in opposition (that
is, when the earth is between it and the sun), has caused its rotation
to be distinctly visible; the observation of this has been from time
to time greatly favoured by certain dark spots which have remained
stationary a sufficient time to determine the question very accurately.
Mars takes 24 hours and 37 minutes to turn on its axis, or pretty
nearly the time the earth does. Its resemblance is still more increased
by the axis of rotation being oblique, from all which it is inferred
that there is a day and night, winter and summer, and variation of
climate very nearly resembling that of our own world, and there are
round bright parts situated at the poles of Mars, which enlarge when it
is winter there and diminish when summer, just as would the snows of
arctic regions, and these are therefore supposed to be portions of the
surface of Mars which are actually covered with snow (fig. 13). As to
the question of the planets being inhabited, of course it can never be
answered with certainty, but it is a great deal more likely that they
are than that the moon is, which, having neither water nor atmosphere,
can hardly be supposed to give habitation to any beings similar or
analogous to those on earth, while Mars possesses a climate not greatly
differing from that of the earth, and has both air and water. Mars
has, at certain positions of the earth with respect to it, a partially
"gibbous" form, that is, a small portion of the non-illuminated part
comes within the lines of our vision it is then of the form seen in
(fig. 14), but this can only occur when the earth and planet occupy
positions somewhat near to that represented in fig. 15, in which S is
the sun, E E opposite positions of the earth, and M Mars.
[Illustration: FIG. 14.]
[Illustration: FIG. 15.]
[Illustration: FIG. 16.]
[Illustration: FIG. 17.]
Jupiter is by far the largest of the planets, it is 87,030 miles
in diameter, and placed at the enormous distance of 494,000,000
miles from the sun. This great planet takes 12 years and 52 days to
perform its circuit; it turns upon its axis in 9 hours 55 minutes, a
surprisingly short time considering the immensity of its bulk. As a
result of this rapid motion Jupiter is very far removed from the form
of a true sphere, for the oblate form of heavenly bodies is caused
by their rotatory motion, and the centrifugal force set up by it. In
fig. 16 is an outline of the earth and Jupiter, showing their relative
size. It has no phases, like those planets which are nearer to the
sun than the earth, its great distance preventing this, as may be
seen in fig. 17, in which the earth (E E) is placed at the
two widest lateral positions of its orbit, but the earth is too near
the sun, in proportion to the great distance of Jupiter, to allow
any part of the latter to come within the range of vision, except
that which is illuminated by the sun. This planet is high up in the
heavens the greater number of nights in the year, and is therefore a
very conspicuous object. It also presents a most beautiful appearance
through a good telescope, its vast size causing it to look larger
than those which are much nearer; it has several shadowy belts across
it, which are supposed to be openings in the strata of clouds which
surround it, drawn into ring-like forms by the rotation of the planet,
these are shown in fig. 18. It being probable that this great planet
is surrounded by strata of the densest clouds which only open in the
tropical region, its inhabitants therefore, (if there be any) get
but a glimpse of the firmanent and its stars through them, in those
situations at or near to the planet's equator. These dense clouds serve
a very useful purpose in regions so very far removed from the source of
heat, for if radiation were permitted to go on freely from the surface
of the planet the sun's rays would be too feeble to compensate for it,
and the cold would be intense; but the clouds reflect back the heat
radiated from the surface and keep in what little heat is received
at that great distance. Jupiter has four satellites or moons, which
revolve round it as our moon does round this earth.
[Illustration: FIG. 18.]
[Illustration: FIG. 19.]
Far beyond Jupiter rolls another stupendous orb called Saturn, not so
large as Jupiter, but still immense, being 847 times the bulk of the
earth. It is placed at the distance of 906 millions of miles from the
sun. An idea of this may be formed from the fact that light, which
travels at the rate of nearly 200,000 miles a second or 12,000,000
a minute, takes about an hour and a quarter to pass from the sun to
Saturn. It performs its journey round the sun only in 29-1/2 years,
which are therefore but as one year, yet all this time it is moving at
the rate of nearly 22,000 miles an hour, so immense is the orbit it
has to traverse, but it revolves on its axis in about 10-1/2 hours,
so that the nights and days are extremely short while the years are
prodigiously long. There is every reason to believe that it has
changes of seasons and variation of climate similar to those in our
world, but, being so far from the sun, they must be altogether more
severe than ours. The most extraordinary part of this great globe is
its possession of three (perhaps more) great flattened rings, which
surround it, one within the other; these rings are of immense size and
width, but very thin, the great breadth through all from the inner to
the outer edges being about 30,000 miles, while their thickness cannot
exceed 250. These rings are placed at a right angle to the planet's
axis of rotation and revolve with it, so that when the planet is at
the equinox, the edge of these rings is turned towards the sun, they
can then be seen only by the most powerful telescopes, forming a faint
streak on each side of the orb of the planet (fig. 19), but as they
become inclined they appear as a very long ellipse, the ends of which
project in loop-like forms on either side, giving rise to the notion of
the planet having two handles (fig. 20). This ellipse becomes broader
and broader as the plane of the rings forms a greater angle with the
line of vision. For a short time before and after the equinoxes of
Saturn, the rings become invisible, owing to the earth and sun being on
opposite sides of them, as may be seen in fig. 21, so that the darkened
side is turned towards the earth and the edge, which is the only part
illuminated, is towards the sun.
[Illustration: FIG. 20.]
[Illustration: FIG. 21.]
The inner ring of Saturn is supposed to be composed of watery vapour,
as it is somewhat transparent, but the outer ones are solid, which
is shown by the shadow they cast upon the planet, and the shadow it
casts upon them in different positions (figs. 22 and 23). Besides
these rings Saturn has eight satellites or moons, which revolve in a
plane nearly parallel to that of the rings and exterior to them. It
has been calculated that Saturn weighs only 100 times more than the
earth, although it is somewhere about 900 times larger, from which it
is concluded that the substance of which Saturn is made must be about
one-ninth the density of this earth, half the density of water, or
about the same as cork. Saturn is very much flattened at the poles, so
much so that the equatorial diameter is a tenth more than the axial
diameter, which difference is distinctly visible through good glasses.
Still further into space, at double the distance of Saturn, or nearly
1822 millions of miles from the sun, another great world or planet
revolves round it, it is called Uranus. This planet is not so large
as either Jupiter or Saturn, but is of considerable magnitude, being
eighty times that of this world, it takes eighty-four of our years to
complete its vast circle round the sun, which are therefore equivalent
to but one year of Uranus.
[Illustration: FIG. 22.]
[Illustration: FIG. 23.]
It has several satellites, four of which have been discerned perfectly,
but it is doubtful whether there have not been two more seen. This orb
was first recognised as a planet by Sir Wm. Herschell, after whom it
was for some time named.
Another, and the most remote planet in our system, is Neptune,
revolving at the immense distance of 2850 millions of miles from the
sun, and taking more than 164 years to perform the journey. This
planet is only to be seen by the most powerful glasses, and was
discovered under very peculiar circumstances, not (like other planets)
by chance; its existence was recognised as necessary to account for
certain "perturbations" or deviations in the orbit of Uranus, which
was found to take a course differing from what it should, according to
computation, and which were only to be accounted for by supposing that
another planet existed far out in space, which affected the course of
Uranus by its attraction. The idea of finding out where this orb should
be, occurred to M. Le Verrier and Mr. Adams, independent of each other;
they both arrived at nearly similar conclusions, for the positions
assigned to the supposed planet so nearly agreed with each other and
with its real position, that their calculations have been looked on as
the greatest feat of astronomical research. It was discovered by Dr.
Galle of Berlin, upon his hearing from Le Verrier the position in which
at that time it should be sought for.
THE PLANETOIDS.
Upon observing the relative distances of the planets from each other in
passing outwards from Mercury, it will be found that each one is placed
about double the distance of the one next before it (not exactly, but
sufficiently near to form a coincidence almost amounting to a law),
they are as follows:--
Mercury 36,700,000
Venus 68,770,000
The Earth 95,000,000
Mars 144,780,000
Jupiter 494,000,000
Saturn 906,000,000
Uranus 1822,000,000
Neptune 2850,000,000
It will be seen, however, that in this table of distances there is
one great exception to the rule, namely the distance between Mars and
Jupiter, which is nearly double what it should be according to this
rule, giving rise to the idea that a planet ought to be placed between
them. Professor Bode was so convinced that something of the kind was
necessary to complete the harmony of the series, that he caused to
be instituted a search for the supposed planet, and according to his
conjecture one was discovered as nearly as possible in the situation
indicated, but upon more accurate information being obtained, this
planet was found to be so small (scarcely 150 miles diameter) that it
could hardly be considered as a planet ranging with the others, and
having so large a space of the heavens to itself; shortly afterwards
another small planet was discovered, having nearly the same orbit. From
time to time others have been discovered, to the number of forty-two,
up to the present date. Dr. Olbers upon discovering the second of
these small bodies, where one great one was anticipated, put forth the
curious hypothesis, that one large planet had really existed there
at some former time, that it had been shattered into pieces by some
accident, such as an internal explosion, and that more of these pieces
would be found; it is curious how accurately this prediction has been
verified.
If we suppose the original planet to have been liquid when shattered
to pieces, it would fully account for the fragments being spherical,
just as globules of mercury assume this form from their own attraction
of gravitation, and that the planets, our own earth amongst them,
are liquid, is very nearly proved by their forms, which are exactly
such as fluid masses rotating on an axis would assume, moreover the
specific gravity of some of the planets is but little more than that of
water, and with respect to our earth, the evidence of internal heat,
increasing as we descend below the surface, &c., show almost beyond
doubt that at the present time it is in a liquid state (molten) covered
over by a few miles' thickness of hardened crust, which bears such
a small proportion to the bulk of the globe, that the whole may be
considered as liquid.
THE STELLAR SYSTEM.
The thousands of stars which spangle the heavens are all part of one
"system;" but it has been found by the aid of the telescope that this
system is but one out of many. Our system of stars occupies a space
somewhat in the form of a thick lens or much-flattened sphere, but
others are of very different forms, and some have but little regularity
of form at all; our sun is one of the stars of this system. It is not
known whether there are planets revolving round the other stars, the
distance being far too great for any telescope to render them visible.
Our sun occupies a somewhat central position in the system. The stars
are classed into sizes, as first magnitude, second magnitude, &c., on
to the thirteenth or fourteenth magnitude, but all beyond the fifth
magnitude (by far the greater number) are only visible by the aid of
the telescope. There are about 5000 stars visible to the naked eye.
But fourteen stars of the first magnitude are in our hemisphere of the
heavens, and about fifty of the second, but the number of stars of each
magnitude increases prodigiously in the higher numbers, so that those
stars capable only of being seen by the aid of powerful telescopes,
amount to many millions; these are chiefly situated in a great belt
which encircles the heavens, called the "Milky Way," which is caused by
the line of vision passing through the breadth of our starry system,
and consequently meeting with a greater number of stars than in other
directions, where it only crosses its thickness.
The other systems of stars, called "nebulæ," from their resemblance
to little clouds, were supposed to consist of luminous matter of but
little density, and which might at some future period be condensed
into stars; but the improved power and construction of telescopes have
enabled astronomers to resolve many of these nebulæ into clusters of
stars, and there is but little doubt that all could be thus resolved,
were the telescope of sufficient power; and thus it appears that in
the infinity of space collections of systems are placed, each one too
distant from the others to be calculated or written in numbers, but
each consisting of thousands of suns many hundred times greater than
this earth, and many millions of miles from each other. What an idea
of space does this afford, and how soon do all our narrow notions of
possibility and impossibility vanish before such facts accomplished by
the hands of God!
[Illustration: FIG. 24.]
[Illustration: FIG. 25.]
Amongst the stars composing our system there are certain conspicuous
groups or constellations, which were named by the earliest astronomers,
and compose a list of the most ridiculous imaginary figures, as useless
to the casual observer of the stars as to the astronomer, and have
not the most distant resemblance to the figures after which they are
named, as for instance the "Great Bear" (Ursa Major) fig. 24. The
grouping of stars into constellations serves, however, to find any
one required (provided the groups on the chart can be identified with
those in the heavens), as for instance the three conspicuous stars
forming "Orion's belt" (fig. 25), from which a line produced eastward
will point to Sirius, the brightest star in the heavens, and another
line produced westward will serve to point out "Aldebaran," also a
star of the first magnitude, &c.; also a line drawn from _a_ to _b_ in
the Great Bear will nearly point to the pole-star--the star situated
nearly (although not exactly) at the pole, or that part of the heavens
which would be indicated by a line drawn through the earth at its axis
of rotation. Amongst the stars scattered over the vault of heaven
there are many which to the naked eye appear single, but which when
seen through the telescope prove to be two stars closely approaching
each other. These "double stars" are of two kinds, "optical" and
"physical;" optical double stars are those which appear to be near
each other merely from the accident of one being placed behind the
other, nearly in a straight line, although in reality at an immense
distance and in no way connected. Physical double stars (usually called
"binary systems") consist of two suns comparatively near each other and
revolving about their common centre of gravity. Sir William Herschell
first discovered their physical connection, and thereby proved that the
great law of gravitation was not confined to our system, but was the
ruling power which controlled and regulated other systems. Astronomers
have calculated the orbits of only fourteen such "binary systems" at
present with any degree of certainty; about a thousand double stars are
known, but only about one hundred "binary systems." In some "binary
systems" the two suns are of different colours; white and purple, red
and green, or yellow and blue. If any planets revolve about such suns,
when situated between the two, what strange phenomena must occur!
Imagine a day during which a red sun had tinted everything crimson,
being succeeded at sunset (not, as with us, by darkness) by the rising
of a green sun, changing the colour of every object from red to green,
and how curious and beautiful must be the shades of light and colour
during the transition from one day to the other. Can anything be
conceived more gorgeous?--no shadow, but every object tinted with a
combination of colours of the most brilliant hues! Triple, quadruple,
and multiple stars are known in abundance, but all probably optically
so, and not in any way connected with each other by attraction.
Others of the stars are called "variable," they are those whose light
gradually diminishes and after a time regains its former brightness;
some of them not only vary in brilliancy but in colour; the cause
of these phenomena is totally unknown, and fortunate will he be who
discovers it; it will be a great stride in the science of astronomy,
for at present everything proposed has been quite inadequate to account
for such phenomena. About 60 of these variable stars are at present
known, but others are constantly being added to the list. Hind has
discovered twenty-one, Pogson seven, and other astronomers have taken
their share in discerning them.
But, of all the heavenly bodies, none have excited so much wonder, and
in former times so much fear, as the Comets. The orbits of these are
for the most part in very eccentric ellipses, some of them comprised
within the limits of our solar system, while those of others extend
millions of miles beyond it, so that they only reappear to us after
hundreds of years. The matter of which these bodies is composed is
certainly not solid, as the smallest telescopic stars may be seen
through the very middle of it, although many thousand miles in
thickness. When comets approach the sun, their substance appears to
become more condensed, and therefore to possess a greater power of
reflecting light. The cause of the "tails" which appear appended to
comets when they approach the sun is not known, but this tail extends
always in a direction from the sun, and passes over many degrees of
the heavens' space. As comets obey strictly the law of gravitation,
they must possess some amount of weight or mass, however small it may
be, and that it is inconceivably small is proved by the fact of comets
having passed close to Jupiter, right amongst his four moons, without
in any way affecting or disturbing their well-known motions; the
comets have, however, been terribly tossed about on such occasions, one
having been totally lost to us by such an occurrence.
Thus it is seen how the same laws of gravity exist throughout all the
infinity of space. The comets traverse our system of suns, and passing
onwards with incredible rapidity, for years upon years, through that
great space beyond it, at last visit some other system--perhaps to be
as much an object of regard and wonderment there as they were here. The
same ray of light which emanated from one of the distant stars of some
one of the clusters situated far out in space, and which has travelled
for thousands of years at the rate of 200,000 miles for every second
of time, serves us here on this globe to distinguish it--it enters the
tube of our telescope and affects our optic nerve; and the Creator who
caused it _there_ to be given off, has _here_ made our senses capable
of perceiving it. Is not this a clear demonstration of the fact, that
one hand has designed the whole; and one Creator provided for all?
THE AIR.
[Illustration: FIG. 2. STORM, WITH HEAVY RAIN.]
[Illustration: FIG. 1.]
The earth is surrounded in all directions by a covering of air about
forty miles in thickness, which bears about the proportion to the
earth itself that a coating one inch thick would to a ball seventeen
feet through, being about 1/200th of its diameter. This air, though
invisible, may at all times be felt while in motion (such is the
wind), and by rapidly passing the hand backwards and forwards it may
be perceived to press against and slightly obstruct it; this air is
composed of about twenty parts oxygen and eighty parts nitrogen,
together with about one part in every thousand of carbonic acid
(consisting of carbon and oxygen in union) and a small proportion of
vapour of carbonate of ammonia (ammonia in union with carbonic acid).
It is the oxygen which enables animals to live in the air, as it is
taken into their systems at every breath, it is thus constantly being
consumed and would ultimately be so far diminished, that they could
live no longer for want of it; but Providence has so arranged, that the
necessary quantity is always being supplied by vegetables (which give
out oxygen) to meet the deficiency. The air, although a gas, is yet
capable of being weighed, of great compressibility, and of expansion
to an unlimited extent, this causes the lower part (near the surface
of the earth) to be much more dense than the upper regions, and those
who have ascended to the tops of high mountains, have described the
difficulty of respiration as being very great, owing to the rarefaction
or lightness of the air. At the surface of the earth it presses with
a weight of about fifteen pounds upon every square inch, but as this
pressure is equal in every direction, it is not felt by us, nor does
it crush the most fragile flower or insect; but, remove the pressure
from one side of anything, and it will be found to press with violence
upon the other. If the air were removed from the inside of a drum, the
weight of the surrounding air would burst in the parchment and fill it.
By way of experiment, fill a large basin with water, take a tumbler
in the left hand and a piece of lighted paper in the right, hold the
lighted paper for a moment under the inverted tumbler and immediately
apply its open mouth to the surface of the water, letting it dip in
about half an inch, the heat expands and consequently gets rid of some
of the air in the tumbler, and as this cools again it resumes its
original bulk; the pressure of the air on the surface of the water in
the basin will force it up into the tumbler and nearly fill it (fig.
1). This is the principle of the barometer, which is a tube entirely
exhausted of air and the weight of the atmosphere forces a column
of mercury (which is many times heavier than water) up to the height
of about twenty-nine inches, according to the weight of the air at
any particular time; this weight varies according to the state of the
weather, whether wet or dry; but the average weight of air is found
to be perfectly stationary, and during the twenty years from 1816 to
1836, it was found at Paris not to have varied 1/1200th of an inch.
Winds or currents of air proceed from several causes; when the sun
shines on a large surface of the earth, it becomes heated and a column
of hot air is pressed upwards, for hot air is lighter than cold, and
the cold air all around, by its weight, forces it up and rushes in to
fill the space; this space may perhaps be many hundred square miles
in extent, so that a current of wind is caused to blow towards this
spot from all the regions round. This is the general state of things
at the equatorial parts of the earth and causes the "trade winds,"
which uniformly blow (the greater part of the year) from both north
and south towards the equator. Another cause of local winds, is the
condensation of vapours into water; when the air over a large region
is saturated with moisture it is greatly expanded by it, and when the
vapour is condensed and falls as rain, the air from the surrounding
parts forces itself in to fill the space occupied by the rain while in
a state of vapour, which is nearly one hundred thousand times greater
than it occupies when in the form of water. There are many causes to
determine the condensation of the vapour, which the atmosphere always
holds in larger or smaller quantities, but cold is the chief agent, for
when a current of air passes over seas or rivers, or the damp surface
of the earth, it becomes loaded with moisture, and being capable of
holding only a certain quantity (less when cold than hot), it follows
that warm air when saturated with moisture must let some of it fall
when it becomes cooled. This may occur from entering a colder region,
or uniting with another current of air colder than itself. In tropical
regions the air is so warm that it takes up a very large quantity
of watery vapour and upon the coming of colder weather, the rainy
season begins and the air empties itself of its superfluous moisture,
causing the most tremendous falls of rain in consequence (fig. 2).
When the clouds are overcharged with moisture in cold climates or in
cold weather, the vapour freezes as it condenses and forms snow, which
under the microscope presents a series of the most beautiful star-like
crystals (fig. 3); the same result is produced by the freezing of the
vapour or fog near to the earth's surface, this is called "hoar-frost,"
which is (like dew) deposited on those parts of the surface most
cooled by radiation. Hail is caused in all probability by the drops
of rain passing through a cold stratum of air and becoming frozen as
they fall. There are many wonderful accounts on record of great masses
of ice falling from the clouds, some of them several feet thick; the
cause of these phenomena (if they ever did occur) is not known. The
curious occurrence of red or green snow, which has sometimes been
known to fall, is owing to the snow being mixed with myriads of minute
cellular plants called the _Protococcus pluvialis_, which in one state
of its existence is green and in another red, and they colour the
snow accordingly. The cause of their sudden accumulation in such vast
quantities is not known, but may be sought for in some peculiar state
of the atmosphere favourable to their growth, which in many places is
prodigiously rapid.
[Illustration: FIG. 3.]
The temperature of the air differs very greatly in different situations
at the surface of the earth, the extreme difference being about 180
degrees; thus in winter, at the poles, the thermometer frequently
stands at 60 degrees below zero, and at the equator, in summer, 120
degrees above, but, in the higher regions of the air, it is even colder
than at the poles, for the sun shining on the earth heats it, and the
air is heated by contact with it; this is its only source of heat, of
which it receives less and less the further it is from the earth, so
that at a distance (depending upon the situation and climate) ranging
from 3,500 to 17,000 feet from the surface, the air is so cold that it
is called "the region of perpetual snow," and all mountains whose tops
reach above this altitude are covered with snow (formed by the freezing
of the rain and vapour) from this point to their summits (fig. 4), and
the sun (although it nearly always shines there, these regions being
above most of the clouds) is not able to melt it, for the radiation of
heat from its surface is greater than its absorption from the sun's
rays, white substances absorbing but very slowly, and rough surfaces
(as the snow) radiating very rapidly.
[Illustration: FIG. 4.]
Dew is caused by condensation of the watery vapour held in the air;
when the sun goes down the radiation continues from the surface of the
earth, and those surfaces which radiate most rapidly, such as fields
of grass, get cooled down below the temperature of the surrounding
air, and therefore cause a condensation of its watery vapour. This
may be imitated by filling a large glass goblet with very cold water,
and bringing it into a very warm room, the outside of the glass vessel
will become covered with dew, although previously quite dry; the same
may be shown by filling a similar glass with water at the ordinary
temperature, taking care that the outside is dry, then stirring in an
ounce or so of nitre or Rochelle salt, which will cause the water to
become cold, and the outside of the glass to be covered, as before,
with dew. Dew falls fastest when there are no clouds in the sky, as
radiation then takes place from the earth into space, and is not
compensated for by a return of radiation from the clouds to the earth.
[Illustration: FIG. 5.]
[Illustration: FIG. 6.]
Clouds are formed by the partial condensation of vapour, and are borne
along by the wind, instead of falling as rain; the reason of their
not falling is this, when the air below the clouds is saturated with
moisture it will absorb no more and the rain falls, but when it is
warm and dry, and passed in a constantly renewed current, then the
vapour is absorbed before it reaches the earth, and is carried off by
the wind. Clouds, therefore, although they often appear stationary,
are constantly altering their form and size, portions being absorbed
while others are being formed. Fogs are the same as clouds, the vapour
arising from wet grass, rivers, &c., being condensed as it ascends,
by a current of cold air passing over them. The fogs in London have a
brown colour, from admixture of smoke, dust, &c., with which the air
is contaminated (fig. 5). Clouds are of various forms and sizes, and
indeed of almost every variety, but certain kinds which are frequently
seen, have received different names. The "cirrhus" comprises all the
feathery white clouds which float high up in the air in fine weather;
the "cumulus" consists of the large mountain-like clouds which are
generally seen in summer; the "stratus," those horizontal layers
of clouds low down in the horizon, so often seen at sunset; and the
"nimbus" is the rain-cloud, of a dark grey or leaden hue, with sharp
well-marked edges (fig. 6).
[Illustration: FIG. 7.]
Clouds are amongst the most beautiful as well as useful things in
nature, and it is one of the greatest proofs of the active benevolence
of God, that all those things which serve man the most, are the most
beautiful to contemplate. Without clouds there would be no rain, and
without this no vegetation. In many parts of the tropical regions there
is little or no rain, and in such parts desert places abound. Clouds
are often of different states of electricity, and when they come near
enough to each other, a transfer of the fluid takes place, accompanied
with a flash of lightning (fig. 7) and a report, although this is not
always heard at the same time that the lightning is seen, as sound does
not travel nearly so fast as light; there is no danger from this kind
of lightning. But it sometimes happens that a cloud in an opposite
state of electricity to the surface of the earth is near enough
to produce a flash of lightning between them, in this case it is
extremely dangerous to be near; but when the thunder is not heard till
some time after the flash is seen, there can be no danger, as it is
then far away. Sound travels at about eleven hundred feet per second,
therefore (in round numbers) it may be known that the lightning is one
mile distant for every five seconds that elapse between the flash and
the thunder. The notion which prevails that iron and steel attract
lightning is entirely erroneous, they do not even conduct it so well as
copper and many other metals.
[Illustration: FIG. 8.]
Lightning conductors (fig. 8) are wires of iron or copper, made to
project above the highest parts of buildings and carried down to the
earth; they have the power of conducting the lightning down without
injury to the building, for electricity (which lightning is) travels
through metallic wires for any distance without disturbance or noise
(as in the electric telegraph), but bad conductors are apt to be burst
and rent by it if it be strong enough, creating flashes of light and
reports. Lightning strikes most readily any projecting substance or
point, the highest point is therefore selected for the protrusion of
the upper part of conductors. In a plain or open space, trees and
animals are often struck, as they form conductors (although very bad
ones) to the lightning; being bad conductors, instead of allowing it to
pass quietly to the earth as do the wires, they are generally destroyed
by it. It has been often stated that we should select an open space
in a thunder-storm, but this would render one liable to be struck,
especially if there were no object near of larger dimensions, the best
plan is to stand near to any trees or houses without touching them, the
danger would not then be so great, the trees or buildings being taller,
would be most liable to conduct the lightning to the earth. The danger
of touching or leaning against a tree in a thunder-storm, arises from
the person thus making himself (as it were) part of it and incurring
the same risk.
Thunder-storms, which would at first thought appear to be of no utility
to man, are indeed of great service; it is a common saying that thunder
clears the air, this is the result of feeling and experience, but
chemists have demonstrated the fact that a substance called "ozone" (a
peculiar state of the element oxygen) is produced by thunder-storms;
this ozone possesses the wonderful power of correcting (decomposing)
putrid and unwholesome gases and exhalations which might otherwise
produce fever, cholera, &c., it moreover destroys the ova or germs
of many animals and vegetables which might otherwise be injurious to
vegetation of more importance, the slight injury which these storms
inflict here and there should weigh as nothing in the balance of
utility with such universal good. Thus it is that the works of God
have all the stamps of goodness, and this ought to inspire us with
so much thankfulness as to overcome every fear for personal safety.
Were these grand phenomena of nature, (as materialists would make
us believe) the result of laws depending solely upon the physical
co-operation of mere matter, good would be the exception instead of
the rule, and most of them would produce effects, if not injurious at
least not beneficial, but such is not the case, and throughout all the
wonderful operations of nature there is not one but tends to good,
for God often inflicts a small injury that a great good may result;
we say a small injury, but it is questionable if the injury is not
often a benefit, which appears to us injurious only because we do not
understand it fully, every disturbing cause tends to produce some
apparent disorder, such as storms, hurricanes, &c., some indeed so
terrific as to destroy ships and houses, but what would be the result
if the atmosphere were never disturbed from any cause? Why the lower
stratum would become so loaded with impurities that it would be unfit
to breathe, miasms and noxious gases would for ever remain a curse
to the races of men and animals who might be doomed to inhabit such
regions, but the very regions where these miasms are most likely to
form are those about the tropics, and here it is that the greatest
storms occur to remove them. Even the great deserts, which appear so
useless to man, and which are uninhabitable to a great extent, have
their office, and an important one too; they are to the earth what
ventilators are to buildings, drawing the cold air from the poles to
cool the regions that are too hot, and sending a current of heated air
through the upper regions of the atmosphere (where it can do no injury
to anything) to warm the colder parts of the earth, another instance
of the wonderful care and goodness on the part of the Creator. The
various and beautiful colours of the clouds, particularly at the rising
and setting of the sun, are caused by refraction separating the white
light into its primitive constituents, blue, red, and yellow light and
their combinations, purple, orange, green, &c., and the more obliquely
the rays impinge upon the earth the greater will be this refraction,
this accounts for colours seldom appearing in the clouds at midday. But
of all the beautiful effects of the refraction of light, the Rainbow
(fig. 9) is the most glorious, it has been celebrated in all ages for
its transient beauty. It is only seen when rain is falling in front of
a brightly illuminated cloud, the sun being behind the spectator; it
is a reflection of the sun by the cloud transmitted through millions
of drops of rain, each of which acts as a prism, and produces rings
of colour; for each of the rays of light (red, blue, and yellow) are
refracted in unequal degrees, and therefore take separate places,
forming the rings of colour seen in the rainbow.
[Illustration: FIG. 9.]
The air is the great source from which all the nourishment of the
organic creation, whether vegetable or animal, is derived; its carbonic
acid is decomposed by the vegetables, which appropriate the carbon,
turning over the oxygen to their companions, the animals; the ammonia
of the air furnishes all the nitrogen of seeds and other nutritious
parts of vegetables, which are eaten by animals; and water, the chief
source of all nutriment, passes first from the air before it enters
the soil, bringing both carbonic acid and ammonia to fertilise it.
That all this nourishment is derived from the air is evidently shown
by the formation and increase of mould in forests which have grown for
centuries; this black mould is nearly all decayed vegetable matter,
formed by the continuous fall and decay of leaves and trees, but which,
instead of diminishing, increases. Now, where does all this come from?
certainly not out of the earth, for it does not contain the necessary
elements. Expose the surface of the bare earth for several centuries,
and first small plants, then larger ones, will grow upon it, until the
state of things described above takes place, the earth being just as
rich in organic matter now as at the beginning, and much richer on the
surface, where a thick stratum of black mould forms from the repeated
fall and decay of leaves and wood; all the substance which the forest
shall have drawn from the earth (with the exception of certain salts
and earthy matters) must therefore have been derived from the air,
which contains every ingredient necessary for its formation, while in
the earth itself no kind of organic matter is ever found.
There was formerly a time when the carbonic acid of the air was in much
greater abundance, and favoured the growth of those plants which thrive
where there is plenty of water, as in swamps and marshes. They grew and
decayed for a vast period of time, till a thick stratum of carbonaceous
matter was deposited, which, after being buried (by some convulsion of
nature) at a great depth, and pressed by the enormous weight of the
superincumbent earth into a hard solid substance, is now being dug up
by man, and forms that most valuable of all products of the mine, coal
(fig. 10).
[Illustration: FIG. 10.]
That coal is derived from decayed and altered vegetable matters,
is pretty well proved; for many pieces of coal, if ground thin and
subjected to the microscope, present a texture exactly such as can be
seen in wood of the present date, and not only the ordinary structure,
but in very many cases certain "dotted fibres," indicating that the
wood belonged to the order of cone-bearing trees (_Coniferæ_), and
there is but little doubt that the constant deposit of such wood and
its slow and gradual decay was the real source of all our coal. How
wonderful, and how good, is the foreknowledge of God! Just at a time
when the great forests of the earth are fast disappearing, and with
them the only other source of fuel for fires, this reserve of the
old forests, which was then useless, serves man as a most excellent
friend--more useful than gold or silver, more precious than diamonds
or rubies! But this world is one of perpetual change, and the coal
thus brought forth from the depths of the earth, is by man being
rapidly restored to the air from whence--thousands of years ago--it was
derived; and it is not coal alone which is thus being restored, but
every organic being in the whole creation, for at their decay they all
enter this vast mausoleum of the dead!
[Illustration]
THE EARTH.
[Illustration]
The Earth, considered as one of those spheres which circulate round
the sun amidst the wide expanse of the firmanent, holds but an
insignificant position among them, especially when compared with those
great and magnificent orbs, Jupiter and Saturn; but, in another point
of view, as the dwelling-place of all the animated beings, vegetables,
and minerals, with which we have any practical knowledge, it holds to
us a position in creation far above all the others.
It is upon the surface of this our earth that we behold in detail
those wonders of the Great Creator's hands, which must fill all
who contemplate and study them with enlarged ideas of His wisdom,
goodness, and power. We see the millions of stars sparkling in the
abyss of space, and our minds are so formed that we can measure and
gauge their distances and rates of travelling, their orbits and their
sizes, their weights, and the powers with which they attract and
influence each other; but we only contemplate a star as one bright and
beautiful object worthy to be one of the gems which the Almighty has
set in His crown of glory, or a lamp to light the halls of His infinite
habitation, but we still contemplate it as a single object; while on
the surface of the earth our Maker has permitted us to roam and search
out by what benevolent contrivances He has suited all things to the
comfort and welfare of His creatures. How His mercy and goodness are
extended amply to the most minute animalcule as well as to man, and how
His powers of construction are to be found in the most minute objects
which the microscope can display, as perfect as in the largest creature
we behold. It is here upon our earth that we perceive how the structure
and functions of all creatures are regulated and controlled by the
unerring laws which He has created, over which laws the creatures
have no control, and which if duly regarded and used according to the
faculties each has been gifted with, will return the greatest joy and
happiness their several natures are capable of, and secure all that
perfection of operation which their mechanical frames are suited to
perform; but before any description of the organised beings which
dwell on the earth can be given, it will be proper to enter into a
description of the earth itself, to see what sort of place God has
provided for them, and how through succeeding cycles of time He has
gradually perfected and prepared it for the reception of His last great
work, Man.
It is only a few miles below the surface of the earth that man has been
able to penetrate and examine, but reason comes to assist him where
examination fails, and it would have been but a few hundred yards only
that his labours could have extended had it not been that parts, which
are generally situated miles below the surface, are occasionally found
at or even raised above it, by some disturbing cause which operated in
times far back; so that man is able to examine on the surface parts
which he could scarcely dig down to.
The whole of the earth, its inhabitants, the air which surrounds it,
the waters upon its surface, and its vegetable products, are composed
of certain substances called elements, combined and united in certain
numbers and proportions. The following is a list of all known:--
METALLIC ELEMENTS.
Aluminium 13.7
Antimony 12.9
Arsenic 75
Barium 68.5
Bismuth 21.3
Cadmium 56
Calcium 20
Cerium 47
Chromium 26.7
Cobalt 29.5
Copper 31.7
Didymium *
Donarium *
Erbium *
Glucinium *
Gold 197
Ilmenium *
Iridium 99
Iron 28
Lanthanium *
Lead 103.7
Lithium 6.5
Magnesium 12.2
Manganese 27.6
Mercury 100
Molybdenum 46
Nickel 29.6
Niobium *
Norium *
Osmium 99.6
Palladium 53.3
Pelopium *
Platinum 98.7
Potassium 39.2
Rhodium 52.2
Ruthenium 52.2
Silicon 21.3
Silver 108.1
Sodium 23
Strontium 43.8
Tantalium 184
Tellurium 64.2
Terbinum *
Thorium 59.6
Tin 59
Titanium 25
Tungsten 95
Uranium 60
Vanadium 68.6
Yttrium 32.2
Zinc 32.6
Zirconium 22.4
NON-METALLIC ELEMENTS.
Boron 10.9
Bromine 80
Carbon 6
Chlorine 35
Fluorine 18.9
Hydrogen 1
Iodine 127.1
Nitrogen 14
Oxygen 8
Phosphorus 32
Sulphur 16
Selenium 39.5
By this list it will be perceived that the greatest number of the
elements are metals, but most of these are very rare and met with but
in certain localities, making up but a very insignificant part of the
earth's surface, while others (never found in nature, as metals) in
combination with oxygen forming "earths" compose the greater part of
its bulk. But of all the elements, oxygen (a gas) is the most widely
diffused, and constitutes rather more than one half of the whole earth,
thus it forms 1/5th of the air, 9/10ths of the water, of the various
earths and rocks about 1/2, and in all organised beings about 3/4.
Of the metallic elements, those which form the greater bulk of the
earth are--
Silicon.
Aluminium.
Calcium.
Magnesium.
Potassium.
Sodium.
These never exist in nature as metals, but combined with oxygen forming
the following earths and alkalies:--
Silica }
Alumina } EARTHS.
Lime }
Magnesia }
Potassa } ALKALIES.
Soda }
These four "earths" form about eighty-five per cent. of the whole
bulk of this globe, the remainder being made up of water (composed of
eight parts oxygen and one part hydrogen), of "salt," both as rock or
crystal-salt, and dissolved in the water of the sea, of the ores of
different metals (metals in union with oxygen, sulphur, &c.), and of
the remains of former vegetation, existing as coal.
Silica is composed of 21.3 parts of silicon with 24 of oxygen, it is
that earth which constitutes a great part of almost every soil, and
forms sand, sandstone, and flint, it enters largely also into the
formation of granite and the other primitive rocks; when pure it is
called "quartz" or "rock-crystal" and is often found in large and
beautiful masses. Silica, in different forms, contaminated and coloured
by different metallic oxides, &c., forms that class of stones known as
"agate," "Scotch pebble," "carnelian," &c., and in the form of flint is
found nearly pure, forming "nodules" or rounded masses lying in layers
in the chalk cliffs on our coasts, the origin of these nodules of flint
is very obscure, but they are by many attributed to the petrifaction of
sponges, &c., the general form of which they often retain as well as
their internal structure, which may be seen when viewed in thin slices
by means of the microscope. Pure silica is a white insoluble powder,
and is much used by the makers of porcelain to mix with their other
ingredients.
Alumina consists of 41.1 parts of aluminium in combination with 24
parts of oxygen, it is the earth which forms the basis of all clays,
loams, and slates, it is in its pure state perfectly white but in most
clays is coloured brown or blueish by oxide of iron, many of our most
beautiful gems, as the ruby, sapphire, and emerald, consist chiefly of
crystallised alumina coloured by oxide of iron, chromium, &c., this
earth like silica enters largely into the composition of the primitive
rocks.
Lime is another of the earths which form a great part of all soils;
it consists of 20 parts calcium with 8 of oxygen. Unlike the two
preceding earths, it exists only in union with some acid. When united
to carbonic acid it forms limestone, chalk, marble, &c., and when in
a crystallised state "Iceland spar." The various kinds of limestone
are largely used as building-stones, and any of them when burnt yields
lime or "quick-lime" as it is generally called, which is capable of
uniting with a certain portion of water, giving out a considerable
amount of heat during the combination. Lime is often found in union
with sulphuric acid, forming gypsum or Plaster of Paris, in combination
with phosphoric acid it forms the basis or earthy part of the bones of
animals, and is found in some of the tissues of plants.
Potassa consists of 39.2 parts potassium in union with 8 oxygen, it
constitutes about 12 per cent. of the granites and basalts (primitive
rocks) in union with silica and alumina, it is also found in the fluids
of many vegetables in union with carbonic, oxalic, and other acids.
Soda consists of twenty-three parts sodium with eight oxygen, it
however does not exist in this form in nature, but in union with
chlorine instead of oxygen, constituting chloride of sodium or common
salt, this substance forms strata of considerable extent in some
localities and being soluble has no doubt been washed out by the rains
from many other places and has thus communicated saltness to the waters
of the ocean. The other metallic elements exist chiefly in those forms
of earth called "ores" being metals in union with oxygen, sulphur, &c.,
or are found in the metallic state, as gold, platinum, &c., it is from
these ores that most of our useful metals are procured by the process
called smelting, as in the case of iron, copper, lead, tin, &c. All
the substances known result from the combinations of the elements, but
these elements do not chemically combine in all proportions, but in
certain definite quantities only; these quantities or proportions are
signified by the numbers attached to each element in the list given,[1]
and the union of these substances must be in the proportion of these
numbers (or multiples of them) only, all superfluity of the substances
combined remaining in a state of mere mechanical mixture. For example,
if six parts of carbon (charcoal) made red-hot be plunged into a jar
containing twenty parts of oxygen, it will unite with sixteen parts
only of the oxygen (a multiple of eight), and form twenty-two parts of
carbonic acid, the extra four parts of oxygen still remaining as oxygen
mixed with the carbonic acid; and if into this carbonic acid twenty
parts of lime be put, it will unite with the twenty-two of carbonic
acid, forming forty-two of carbonate of lime, still leaving the four
parts of oxygen untouched. Had forty parts of lime been put into the
mixture, instead of twenty, still only forty-two of carbonate of lime
would have been formed, and the other twenty parts (like the four of
oxygen) being superfluous, would still have remained as lime, mixed
with the carbonate of lime. These combining quantities are called the
"equivalents" of the substances.
[Footnote 1: See the list of the elements at page 45; those
which are distinguished by an asterisk, are elements of which the
"equivalents" are not known.]
Upon examining various portions of the earth's surface, they will be
found to differ in character from each other; in one place perhaps
sandy soil will be found, in another, hard rock, in a third, clay, in
a fourth, chalk, and so on. Now, if this examination were carried no
further, it might well be presumed that each of these kinds of soil
were continued downwards into the earth for an indefinite distance,
but upon digging (as in sinking a shaft or well) it is found that the
stratum of soil upon the surface is soon passed through, that others
in succession present themselves and that this succession of strata
is not a matter of chance, but (with certain restrictions) follows in
invariable order. It is true some strata are occasionally not present,
and that others replace them; but yet (taken altogether) there is the
same order of succession everywhere found. The following diagram (fig.
1) gives the section of these strata from the earth's surface to the
granite which is the lowest of all formations and through which no
one has ever penetrated. The figures give an approximation to their
average thickness in feet. These strata do not all run in a direction
parallel to the surface of the earth, or else it would result that the
surface would everywhere be made up of the highest, but they have been
contorted and heaved up into mounds or depressed; and the granite has
often been pushed upwards, carrying with it all the upper strata to a
certain extent, at last thrusting quite through them all and presenting
itself above the surface, forming in this way the tops of many very
high mountains, Mont Blanc for instance. Such a mountain if cleft from
the summit to the base would present a section similar to that shown
in fig. 2, and thus it occurs (contrary to what would at first thought
be supposed) that the highest ground is generally formed of the lowest
strata, while the valleys are nearly always covered with the latest
formations, which is partly owing to the elevating process before
alluded to, and partly to the winds, rains, &c., tending to carry away
and wash down every kind of soil from the upper ground and deposit it
in the lower.
[Illustration: FIG. 1.--DIAGRAM SHOWING THE POSITIONS AND RELATIVE
THICKNESSES OF THE STRATA.]
[Illustration: _Granite_ FIG. 2.]
[Illustration: FIG. 3.]
[Illustration: FIG. 4.]
[Illustration: FIG. 5.]
Fig. 3 represents strata in a state called by geologists
"conformable," which name is applied when the strata follow their
natural or regular succession, whether this retains its horizontal
position, or, as in fig. 4, assumes a position more or less
vertical, which frequently happens from the subsidence of one
part or the elevation of another; but they are sometimes found in
the state represented in fig. 5, and in which they are said to be
"unconformable." Such strata after having been tilted out of the
horizontal have had other strata deposited upon them, which again
may be more or less contorted from the same causes. The regularity of
strata is often interrupted by what are called "faults" or "dykes,"
which have arisen from some part of the earth sinking down or another
part being raised up, producing a fracture through all the strata and
causing those on either side of this fault or fracture to occupy a
situation not corresponding to those on the opposite, as in fig. 6, but
yet to be found at a higher or lower elevation, and it is nearly always
found that these strata are raised on that side to which the line of
fracture inclines, as in the figure. These faults are often sources of
great annoyance to the miner, who finds a sudden termination to the
seam of coal or ore that he is working. The cracks are generally filled
with some primitive rock, as basalt, rising from beneath while in a
liquid state and filling up the interstices; it will often happen that
the faults thus filled will have veins of the same rock branching out
and not only filling up cracks but forcing its way between the various
strata, thus interposing a stratum of basalt quite out of its proper
position and altering, by the effects of the heat communicated, the
character of the strata in juxtaposition; this is shown in fig. 7.
[Illustration: FIG. 6.]
Upon a close examination of the various strata which form the crust of
the earth, it is found that each has its own peculiar character; some
have resulted from the accumulation of matters deposited at the bottom
of ancient seas, others in the beds of rivers or fresh-water lakes, or
again others (as the coal formation) from the accumulation of vegetable
matters; further, these strata do not only differ in structure and
composition, but also in the remains of animals and plants found in
them; for there is scarcely any kind of soil (above the primary rocks)
in which abundant remains of these have not been found. It will now be
proper to give a description of them in succession, beginning at the
lowest or primary, _granite_.
[Illustration: FIG. 7.]
This appears to be the result of the cooling and crystallisation of
that molten mass which many circumstances (hereafter to be mentioned)
point out as making up the great body of the earth. Granite differs,
in various places, in colour and quality (the varieties are known as
"sienite," "porphyry," "greenstone," &c.), but still retains its own
distinctive characters; it is a hard, crystalline rock, consisting of
"felspar," "mica," and "quartz," in separate crystals, but mechanically
blended; its chemical composition as a whole is silica, alumina,
and potassa, with small quantities of lime and oxide of iron. This
granite is met with everywhere, if the outer crust of the earth be
penetrated to a sufficient depth; it however frequently exists on the
surface, having no strata below it, and in some places overlies other
strata--this, and the fact that cracks and crevices of some of the
lower strata are filled up with granite, which could only have taken
place while it was in a liquid state, as in fig. 8, together with
evidences of the effects of calcination, and other changes producible
only by extreme heat, all around those parts and in the strata
immediately overlaying the granite, point out that it was once in a
state of fusion.
Above the granite formation, in many places, especially in Norway and
Sweden, there is a stratum of rock called _gneiss_, which consists of
the same ingredients as granite in a slightly altered form. Granite
will often pass into gneiss gradually, and this again into those slaty
formations which rest upon it and come next in the series. These
consist of mica-slate, hornblend-slate, and chlorite-slate or schist,
a name given to all those rocks of a slaty structure which have a
cleavage or capability of being cleft into thin laminæ or slices (hence
their applicability to the purposes of building, forming excellent
roofing materials, &c.).
[Illustration: _Granite_ FIG. 8.]
All these rocks have received the name of "primary," they have no
appearance of being stratified or deposited in layers, which appearance
seems to be in all cases the result of having at some time been
suspended in water and thence deposited gradually as mud, sand, &c.,
time, pressure, and heat having afterwards altered their consistence.
All these consist of the earths described as composing granite,
but combined in different proportions. Above these rocks there is
a formation of a totally different composition, namely crystalline
limestone, commonly known as marble; this consists wholly of carbonate
of lime or lime in union with carbonic acid, and its crystalline state
appears to have been produced by long-continued heat and pressure.
This limestone is by many ranked amongst the primary rocks, although
it differs so entirely in its composition which exactly resembles a
formation presently to be described (the chalk); however, if this be
classed with the primary rocks, then it may be fairly said that all
above have resulted from their disintegration and reunion in different
forms, by the action of water and vital forces of different kinds. The
state of the earth at the close of this the "primary period" may now
be considered.
The early history of our globe forms one of the great problems of
geology, but there is evidence enough upon which to form conclusions
and show that the earth had undergone some great and varied changes
embracing immense periods of time, and if the sciences of astronomy,
chemistry, mathematics, &c., be brought in to assist the inquiry, some
plain facts become evident. Astronomy shows us orbs circulating round
the sun (the planets), strictly analogous to our earth, and furnishes
us with their densities; these are found to be various, ranging from
about six times the density of water to half its density. The planets
appear to be at different stages of condensation, and it is not
unreasonable to suppose that our earth was once of no greater density
than the lightest of them. The inner ring of Saturn is probably in a
liquid state, for it is transparent. The substance of which comets
are composed is a vapour, so rare and thin that it cannot be compared
in density to our atmosphere even, and yet these comets preserve
their identity, circulating through immense realms of space with
prodigious rapidity. Thus astronomy presents analogies in favour of
the supposition that the earth was once gaseous, or at all events of
much less density than at present; but mathematical inquiries go much
further, and furnish almost proof that the earth was once (if not now)
in a liquid state, for the exact form which a liquid ball would assume
upon rotating at the rate which the earth does, is exactly that which
the globe is found by measurement to possess.
Chemistry has ascertained that the heat of the earth is far greater
than any tract of the heavens through which it passes; that this heat
could not have been communicated by the sun's rays, for had it been
so the surface would be hotter than the interior, the very reverse of
which is found to be the fact, and the deeper we go down the higher
the temperature is. Chemistry shows further that this heat can be
completely accounted for by the condensation and solidification of the
earth itself; for the condensation of all gases into liquids, and of
liquids into solids, causes a very large portion of latent caloric to
become sensible, for example, any quantity of a gas at 60 deg. suddenly
reduced to a smaller bulk, would have a temperature higher than 60
deg. A little contrivance has long been in use for obtaining fire by
this process, consisting of a cylinder and piston, the rod of which
if struck down sets fire to a piece of German-tinder. It is probable
that all fire, and every alteration of temperature, are due to this one
cause alone.
Now assuming it as a fact that the earth was once in a gaseous state,
and that the atoms of this gas or vapour exerted (as they must have
done) an attraction towards each other, the result would be that they
would press immensely upon those parts towards the centre and cause
them to solidify. This act of solidification would produce such an
intense heat that the solid would be expanded and fused into a liquid,
this continuing until all the more condensible matters had become
liquid, the earth would assume its spheroidal form from its rotation,
be surrounded by an atmosphere of the least easily condensible
substance, nitrogen, together with all the oxygen not wanted to
combine with the metallic vapour and form earth. This globe with its
atmosphere continuing to roll through the cold regions of space, would
gradually lose the heat from its outer part by radiation. A film of
cooled and condensed earthy matter would begin to form on the surface
by crystallisation, and then would commence all those grand phenomena
which it is the province of the geologist to study and explain. This
crust consisted of the first-formed granite which (from inequality of
contraction in the bulk of the earth) was broken up into fragments
and perhaps partly re-dissolved again and again in some places, as it
chanced that these contractions were more or less irregular. The result
of this crushing and crumbling-up is seen in the coarser parts of the
gneiss, called "Grauwacke," which consist of angular fragments of
granite more or less imbedded in a cement of the same substance. This
could not have been produced by water, as the surface must have been
too hot for it to have existed on the earth in any other form than the
most highly rarefied steam combined with the atmosphere, and in all
probability partly condensed in the upper regions, forming a continuous
strata of clouds, or rather water, through which the sun could hardly
be seen or its light penetrate, and such a state of things exists at
this present time in the planet Jupiter. How beautifully does this
coincide with the Mosaic account, "The earth was without form and void,
and darkness was upon the face of the earth."
The surface of the earth at this time can be well understood by any
one who will take the pains to evaporate any saline solution in a
capsule till it is about to crystallise, and observe attentively the
pellicle of salt as it forms on the surface; first a partial film will
show itself in a few places, floating about and joining with others,
then when nearly the whole surface is coated, it will break up in some
places and sink into the liquid beneath, another pellicle will form and
join with the remains of the first, and as this thickens it will push
up ridges and inequalities of the surface from openings and fissures
in which little jets of steam and fluid will escape; these little
ridges are chains of mountains, the little jets of steam those volcanic
eruptions which were at that period so frequent; the surface of the
capsule is the surface of the earth, and the five minutes which the
observer has contemplated it, a million years.
The next effect of the cooling of the earth would be the gradual
condensation of the vapour of water with which it was surrounded; this
falling upon the earth formed seas and oceans, leaving only the higher
portions exposed above its level. The clearing-up of the dense dark
clouds for the first time let in to the earth's surface the glorious
and vivifying rays of the sun, and this great effect possibly accords
with the earliest record in the Bible of the acts of creation--"And God
said, let there be light, and there was light."
[Illustration: FIG. 9--STALAGMITE.]
[Illustration: FIG. 10.--TEREBRATULA.]
The earth being chiefly covered with water, and the air partly freed
from watery vapour, then commenced the great creation of organised
beings. The air, although to a certain extent, free from vapour, must
yet have contained an enormous amount of carbonic acid; this, being
less easily condensed than any of the matters which had gone through
that process, would still remain there as a gas, and the effect of this
superabundance would be to saturate all the water covering the earth
with it; this solution of carbonic acid, being capable of dissolving
lime, would (as it percolated and rushed in currents through the rocks
and inequalities of the surface) become converted into a solution of
percarbonate of lime, taking up a large quantity of this earth from
the broken-up granite, &c., then this carbonate of lime would be
deposited at the bottom of the water in one of two ways--either from
pressure, diminution of carbonic acid in the air, and heat of the
surface, it crystallised at the bottom in the form of marble (that
the water does thus become saturated with carbonic acid and take up
lime, is constantly shown by the stalagmites which form on the floors
of caverns, where the water thus loaded with percarbonate of lime,
evaporating, deposits gradually the carbonate in all sorts of fantastic
shapes, as in fig. 9), or the myriads of crinoidians and brachiopodous
molluscs (fig. 10) which were about this time created, absorbed it into
their systems and at their death deposited their shells, which are made
of this earth, at the bottom of the sea; these shells, accumulating
through ages into strata, became hardened and partly crystallised by
heat, thus forming the limestones, which were the first containing
carbonate of lime. That such a collection, from such causes, is quite
possible, will be presently shown in describing the chalk formation.
Ages of comparative quiet now appear to have succeeded the first great
contraction of the earth's crust, probably millions of years, during
which time the tides and currents of the ocean had to wash and wear
down all the thousands of projecting rocks or inequalities and dissolve
(as before described) all the lime, depositing the sand and clay in
those immense strata which form the "transition series;" this appears
to have taken place over nearly the whole world at that time, and ages
upon ages must have elapsed to form such deposits as the sandstone,
claystone, and limestone, in alternation, forming the "Llandilo,"
"Caradoc," and "Wenlock" strata, more than a mile in thickness; these
are by some geologists reckoned among the primary series (by some
called the "transition rocks"), and in England form the "Cambrian" and
"Silurian" systems.
[Illustration: FIG. 11--TRILOBITE.]
In these strata the remains of organised beings are first found,
consisting of zoophytes, crustacea (chiefly Trilobites, fig. 11),
nautili, crinoidii (stone lilies), and a few ganoid (plate-covered)
fishes; these lower forms of animal life in some parts abound in the
most prodigious numbers. There must, of course, have been vegetables
of some kind previously formed to constitute nourishment for these
animals, but scarcely any remains of such exist, except in a few
localities.
The Trilobites were amongst the first creatures inhabiting our globe,
and it is a curious fact to contemplate, that their eyes (fig. 12)
should have been preserved perfect; they present one of those
wonderful objects which carry one's thoughts backwards to the early
ages of the world, probably many millions of years, and yet it is
found by the peculiar structure of the eyes of these Trilobites that
they were placed at the bottom of the sea with perfect power to look
upwards at the light of the sun through the transparent waters. The
same hand and the same power had then Divine care and solicitude for
the well-being of His creatures, as great as He has for those of later
ages, and these first-formed beings exactly correspond with the account
of the creation of animals given in the book of Genesis, "And God said,
let the waters bring forth abundantly the moving creature that hath
life."
[Illustration: FIG. 12.--EYE OF TRILOBITE.]
At the end of the "transition period"--after ages of long-continued
disintegration of the rough surface of the earth, and its deposition in
strata--after thousands of generations of crustaceans, molluscs, and
zoophytes had lived and died, depositing their shells at the bottom
of the seas, so as to form strata of the carbonate of lime--a great
and terrific convulsion of nature put a stop to all this quiet and
systematic order of things; for through these long reaches of time,
the physical laws of nature had continued to exert their influence,
the bulk of the world had gone on radiating its heat into space, and,
as a necessary result, had gradually contracted in size. Now, this
radiation had doubtless been much retarded by the badly-conducting
surface of solid matter which had everywhere covered it, but, although
retarded, it could not be prevented, and although the crust of solid
matter may already have been several miles in thickness, yet this in
relation to the bulk of the earth would hold but the proportion of the
paper on the surface of a twelve-inch globe. As the fluid mass of the
earth continued to contract, there would of course be a great stress
or crushing-power exerted on the crust, both by its own gravity and
that of the air which surrounded it, and about this period it appears
to have given way over the greatest portion of the globe, producing
enormous rents and fractures, seen in every country in the faults
and dislocations of these primitive and transition strata, some of
which were driven up by the downward force of others, and left in a
perpendicular position, some overlapping each other, &c.; but the
greatest effect of this convulsion appears to have been produced by
the rocking or rolling surface of the sub-existing fluid world,
forming gigantic waves, which, by meeting in opposite directions and
thrusting upwards the strata to a great height, formed the mighty
mountain-chains of the now-existing earth, which raise their lofty
pinnacles above the clouds. Now, these mountains may at first thought
appear too ponderous and extensive to be thrown up in this way; but by
inspecting the engraved section of a part of the globe (fig. 13), it
will be seen how very insignificant a mountain is when compared with
the whole world. This section is through Asia from the Persian Gulf to
the Yellow Sea, and embraces the highest land on the whole face of the
earth, and is drawn on a scale in which the earth is represented by
a globe sixteen inches diameter. The rugged and peaked tops of these
mountains would be formed by the great fractured masses of the broken
strata being thrust upwards and there resting against each other;
but who can describe the chasms and hollows which must have resulted
when the great wave of melted earth had subsided to its level under
one of these huge mountain masses? or the dreadful abyss into which
at some future time it and the surrounding country may fall, if they
have not already been filled up by the sinking of the surrounding
strata. Some of these great waves, when thrust upwards, forced their
way right through the point of the mountain and came pouring down in
torrents of liquid earth (lava), deluging the surrounding country and
filling up the beds of the adjacent seas, casting out cinders and ores
of metals--as iron, which appears to have first made its appearance
at that time, mingling with the deposits and tinging them of a red
colour. These great volcanoes, upon the subsidence of the rock-waves,
still (more or less) retained their communication with the interior
fiery earth, and are now the greatest safeguards against such a general
crushing-up of the strata, for they act as safety-valves against any
unequal expansion of the interior (fig. 14). The greatest eruptions of
volcanoes or the most terrific earthquakes of modern times, are as the
most insignificant trifles compared with what must have taken place to
form the inequalities of surface found to exist.
[Illustration:
FIG. 13--SECTION OF 40 DEG. OF THE EARTH'S SURFACE, BEING
THE SOUTHERN PART OF ASIA, AND INCLUDING THE HIGHEST LAND IN THE
WORLD.
The outer uneven line represents the mountains and table-lands from the
sea's level, and the lower line shows the depth to which the crust of
the earth's surface has been examined--about five miles.
A to B.--Level of sea.
B to second C.--Hindustan.
C to D.--Thibet.
D to E.--Great Desert of Gobi.
F.--500 miles of Earth's radius.
C to C.--The Himalayas, in which occurs the highest mountain in the
world, Dhawalagiri, which is 28,174 feet high.]
[Illustration: FIG. 14.--BURNING MOUNTAIN.]
But the contraction of the interior mass of the earth still continues,
and the cavities left by the expulsion of volcanic matters, and the
pushing-up of the mountains, may not all have been compensated for by
the sinking-in of the strata, so it remains a matter of doubt whether
the crust of the earth is sufficiently strong to bear the pressure of
its own and the air's gravity, or whether at some future day another
contraction will break it up and destroy the whole existing order
of things. The shocks of earthquakes are strictly analogous to such
catastrophes, but on an immensely inferior scale.
[Illustration: FIG. 15.--LIMESTONE MADE UP OF ENCRINITE.]
[Illustration: FIG. 16.--LIMESTONE MADE UP OF CORALS
(Favosites polymorpha).]
The effects of the last great contraction having subsided the surface
of the earth assumed a new arrangement of its matter, and the order of
things which caused the deposition of the secondary strata commenced.
Sedimentary sandstones were deposited from the washings of the
surface by the waters which had not yet absorbed all the superfluous
carbonic acid of the air, but continued to do so, and as fast as
it became absorbed and saturated with the calcareous matter of the
soil, swarms of coral-polypi, which were then formed, began to build
their habitations in the warm waters of the ocean and rob them of
the carbonate of lime which they contained, leaving them capable of
absorbing more from the atmosphere. These little creatures formed
immense masses of coral, and together with the "Encrinites" (having
stony frameworks, figs. 15 and 16), were the chief artificers of that
age, and well did they show what perseverance was able to accomplish,
for through the thousands of years of quiet which now succeeded,
they must have filled up nearly all the existing oceans with their
structures, causing the water gradually to flow from its former beds
into other situations, and thus from time to time was changed the
position of both sea and land. The strata of mountain limestone which
now exist are the remains of what these little polypi then produced,
for there is scarcely a portion of this kind of rock, but shows
evidences of having been, once, coral, madrapore, or some analogous
structure (fig. 17). This mountain limestone sometimes occurs thousands
of feet thick, and extends over vast districts both in Europe and
America.
[Illustration: FIG. 17.--ENCRINITIC LIMESTONE.]
During this period, although there were no great disturbances, capable
of displacing the strata, yet there appears to have been frequent
small eruptions of volcanic matter through the crevices of the lower
strata, filling up all their cracks and vacuities, and in many cases
rising to the surface, overflowing with basalt, toadstone, and other
volcanic formations; in other cases rising in enormous quantities
through openings at the bottom of the seas, partly filling these up,
driving off the waters, and thus covering many of the coral formations
with coatings of sand to a great thickness, raising up others into
considerable elevations, and forming hills and fresh tracts of earth.
[Illustration: FIG. 18.--FOSSIL TREE FERNS.]
During this long period of comparative quiet most of the irregularities
on the surface of the earth became worn down, and extensive swamps were
produced by partial evaporation of the inland lakes. These swamps were
subject to occasional inroads of the sea, and at times formed shallow
lakes or lagoons; in these grew the most luxuriant vegetation, gigantic
pines, tree-ferns (fig. 18), equisetacæ, &c. These plants, nurtured by
a hot and moist climate, acquired a great luxuriance of growth, and
must have formed forests of such great density, that there is nothing
existing at the present time worthy to be compared with them, even in
the hottest climates. Such fertility appears to have been dependent
upon the conditions of the air and earth, the former containing more
carbonic acid (the food of vegetables) and the latter a greater amount
of warmth, than at present; these two circumstances, so favourable to
the growth of plants, were equally unfavourable to the existence of
air-breathing animals, to whom the carbonic acid would be fatal poison.
Thus, in the mighty hands of God, the air was undergoing a gradual
purification, to fit it for the animals He intended to create; the
polypi were extracting from the water all the carbonate of lime it
was absorbing from the air and earth, and fixing it in the soil, to
be of use in a hundred ways at some future time, while the vegetation
growing in abundance extracted it from the air, and fixed its carbon
in their leaves and substance generally; these vegetables, decaying
and falling upon the surface of the earth, accumulated there for ages,
and formed a carbonaceous matter which was afterwards changed by time
and pressure into coal. The same thing (on a very much smaller scale)
is taking place in the tropical forests of the present age; there the
surface-soil is quite black, and consists of nothing but decayed leaves
and wood for several feet in depth, but in the present time there are
hosts of insects, every one of which feeds upon this vegetable matter,
preventing to a great extent its accumulation, while in the former age
there was nothing to destroy it when once deposited on the ground; so
that the carbon of these forests of the secondary period, existing
through perhaps tens of thousands of years, extracted from the air a
sufficient quantity of vegetable carbonaceous matter to produce thick
seams of coal, even when compressed by the superincumbent strata.
These forests were subject from time to time to inroads of the sea
produced by the before-mentioned causes, and thus it is found that
the seams of coal are often buried by several hundred feet of sand,
clay, shale, &c., above which the same growth recommenced to form a
second strata of coal, and ages must have elapsed whilst each of the
numerous seams which interstratify the "coal measures" were forming.
This coal, preserved in the depths of the earth, now forms the greatest
treasure of the mine, and ironstone (from which iron is procured)
would be almost useless but for the occurrence of these two minerals
together with limestone (used as a flux) in the same locality, and
it is this fortunate circumstance which enables England to produce
such vast quantities of iron at such a cheap rate. The quantity of
coal consumed in the iron-smelting works and for fuel generally, is
beyond what could have been imagined a generation or two back, being
somewhere about 50,000,000 tons annually, the coal brought to London
alone in 1856 being 1,271,800 tons, yet there is such a plentiful
supply of this valuable fuel in Great Britain alone that, supposing the
annual consumption to rise to 70,000,000, it would serve (according
to computation) a thousand years. Who shall say from whence fuel
will then be obtained? probably from some other source provided by
the foreknowledge of God, as was shown in the formation of the coal
itself; for who could have imagined, a thousand years ago, when England
possessed such immense forests, and wood was the universal fuel, that
this very wood would become too scarce and valuable to be used, and
that a substitute would be dug out of the earth!
The coal-shales (thin layers of claystone found in the coal seams)
furnish beautiful specimens of ferns and other plants turned into coal
(fig. 19), or leaving their perfect impressions in the clay. The coal
formation occurred during the latter part of one of those long eras of
tranquillity which supervened upon the contraction and breaking-up of
the older strata; but the laws of nature are immutable, and these days
of comparative quiet again came to a close. The same phenomena before
described again occurred, and there is hardly a square mile of these
strata but shows evidences of the terrible convulsion which desolated
the earth. Some of the strata were raised, others depressed, and some
lost altogether, the cracks and flaws being filled with liquid lava or
basalt, which in many cases rose upwards through them and overflowed
the surface. Many of the cracks of this, the "carboniferous system,"
are filled with sulphuret of lead called "galena," the ore from which
all the lead of commerce is obtained; it is not well known how the
veins of this and similar substances got into these crevices, but it is
probable they were injected in a fluid state by some unequal pressure
on the liquid beneath, or deposited by electrical action.
[Illustration: FIG. 19.--FERN (Pecopteris ligata) FROM UPPER SHALE,
SCARBOROUGH.]
The great world of vegetation was thus destroyed, giving place to
new forms of animal and vegetable life. The temperature, all this
while sinking, had reached a degree somewhat resembling the hottest
regions of the earth at the present day. The waters had changed their
localities, new mountains and new continents had made their appearance,
and again did the ever-active waters begin to demolish and wear down
the asperities of the surface and deposit the results upon the strata
below in the form of the new red sandstone and magnesian limestone,
the former containing iron in great abundance, and the latter magnesia
(an earth not met with before), both of which substances were probably
ejected as volcanic products and afterwards combined with the carbonic
acid of the air.
[Illustration: FIG. 20.--LABYRINTHODON.]
[Illustration: FIG. 21.--IMPRESSIONS OF FEET IN NEW RED SANDSTONE.]
During the formation of these strata there appears to have been both
birds and quadrupeds of many kinds, together with a reptile much
resembling a frog, but of great size, being five or six feet long,
called the "Labyrinthodon" (fig. 20). The oxide of iron, or some other
agent appears to have prevented the fossilisation of the inhabitants of
these strata, for but few of their organic remains have been preserved;
but very curious evidences of their existence nevertheless remain,
in the impressions of their feet upon the ground they trod (fig. 21),
which appears to have been a moist clay or mud peculiarly adapted to
receive impressions, and which having been in many places covered over
with a stratum of fine sand, and then abandoned by the sea, the whole
have hardened into stone, and being now separated, the one contains
their footprints and the other perfect casts of them! Nor are these
foot-marks all that these sandstones have to tell us of their day;
for the ripples of the waves, and even the little pits made by drops
of rain as they fell, are in this most marvellous manner preserved,
forming objects of wonder and admiration for us mortals to contemplate,
and themes whereon the devout mind may pour out its tribute of praise
to their Great Author. How evident it is that the Creator designed
beforehand that we should search for these hidden evidences of His
handiwork, or for what purpose were they thus stored up and preserved?
"Seek, and ye shall find, knock, and it shall be opened unto you," are
the words of God, and they apply as fully to the material wonders of
His works as to the mysteries of His revealed Word.
As the strata below the new sandstone formation was called the
"Carboniferous" system, from its containing much carbon in the
form both of coal and carbonic acid, so this has been called the
"Saliferous" system, from the occurrence in many places of strata of
"rock-salt" or crystallised chloride of sodium, and (where the rain
finds its way down and dissolves it) of brine springs; these (in
England) exist chiefly in Cheshire and Warwickshire, but in Poland and
Hungary they exist on a much larger scale, the rock-salt being nearly
a thousand feet thick. It has been said that these strata of salt were
formed by the evaporation of salt lakes, but it is much more probable
that salt is one of the natural materials of the earth, and that both
salt lakes and oceans have become salt from dissolving out these strata
wherever they have come into contact. The next sediment deposited
over the new red sandstone is called the "Lias," a sort of limestone
mixed with clay of a blueish-grey colour, and upon this has is again
deposited the various strata known as the "Oolite" (Roe-stone) system,
from its appearance resembling the roe of a fish, it consists of small
rounded particles of limestone set in a cement of the same substance
worn down fine.
[Illustration: FIG. 22.--AMMONITE (Henlyi).]
[Illustration: FIG. 23.--PENTACRINITE.]
These strata furnish a great many organic remains, especially the
shells of the conchiferous mollusca and cephalopods, as Ammonites (fig.
22), Belemnites, Nautili, and Pentacrinites (fig. 23), of which a great
many varieties are found, also the remains of gigantic reptiles, as the
Ichthyosaurus (fig. 24), Plesiosaurus (fig. 25), and others. New forms
of animal existence seem to have been created in this period in great
abundance, and the waters of the earth once again became the theatre of
deposition for the shells and polypidomes of zoophytes and molluscs,
which swarmed them in myriads, and another great group of rocks began
to be formed, namely, the chalk or "Cretaceous" system, which form the
cliffs and downs of our south coasts, and strata of great extent in
nearly every part of the world; it differs from limestone only in not
being so hard, which is supposed to arise from its not having undergone
the changes caused by heat and pressure.
[Illustration: FIG. 24.--ICHTHYOSAURUS.]
[Illustration: FIG. 25.--PLESIOSAURUS.]
[Illustration: FIG. 26.--NAUTILUS INEQUALIS.]
[Illustration: FIG. 27.--ORGANISMS FROM CHALK.]
The chalk is interstratifìed with lines of sand, and the lower part is
almost entirely sandy, forming the gault and greensand deposits; these
each contain organic remains, and must have been the original sand of
the sea-bottom before the chalk was deposited on it. These seas must
have been the residence of a vast number of reptiles, for the gault
contains an enormous number of nodules of what appears to be stone,
but which upon closer examination, prove to be coprolites, or portions
of the excrement of those creatures partly fossilised, but still
retaining phosphate of lime enough to render them valuable manure, and
these--like the coal--after being buried in the earth for thousands
of years, are now being brought into use. In these coprolites may be
constantly seen the teeth and bones of fishes, together with portions
of echini and crustaceans, which had passed through the intestines
of these saurian reptiles. Fig. 26 is the shell of a small nautilus
(_Nautilus inequalis_) thus found.
[Illustration: FIG. 28.--AMMONITE FROM THE CHALK.]
This chalk is of a white colour, very light and porous; under the
higher powers of the microscope, it appears to be made up of organic
forms, as "Foraminifera," and portions of various kinds of shells,
crushed and broken into minute fragments (fig. 27). Dr. Carpenter,
in his work on the microscope, says: "Many parts of it (the chalk)
consist in a great measure of the minuter parts of the smaller kinds
of Foraminifera, whose shells are imbedded in a mass of apparently
amorphous particles, many of which nevertheless present indications of
being the worn fragments of similar shells, or of larger calcareous
organisms. In the chalk of some localities, Foraminifera constitute the
principal part of the minute organisms which can be recognised with the
microscope; in other instances the disintegrated prisms of Pinnæ, or
other large shells of the like structure (as Inoceramus), constitute
the great bulk." The fossil remains in the chalk are very numerous and
are all of a marine character, the ammonites (fig. 28), belemnites,
and other cephalopods, were very prevalent, as were the various
Echinodermata, as the _Hemicidarus intermedia_ (fig. 29), together
with numerous univalve and bivalve mollusca, various crustacea, fish
and reptiles. There was some considerable wonderment a few years
ago expressed at the skeletons of men being found in the chalk at
Guadaloupe; but it has been ascertained that this chalk is a modern
formation, being produced by the sea washing and disintegrating the
adjacent coral reefs, and depositing a fine white sediment of broken
coral on the shore which can hardly be distinguished from ancient
chalk; the same process is taking place at the Bermudas and other
islands of the West Indies.
[Illustration: FIG. 29.--ECHINUS (Hemicidarus intermedia, Chalk).]
In many places the chalk strata contain single lines of flints,
running for miles parallel to the layers of chalk; these flints
consist of almost pure silica, and it has been, matter of wonder how
they got there, but on considering how slowly the deposition of chalk
must have taken place, from the formation and death of millions of
minute creatures, and that it was once the bottom of a deep sea, the
disposition of the flints in lines would be accounted for, supposing
them to have been formed on that sea-bottom, and the source from which
they have been derived is doubtless the petrifaction of sponges,
madrapores, &c., there formed. Dr. Carpenter (in the work before
referred to) says: "It may be stated, as a fact beyond all question,
that nodular flint and other analogous concretions (such as agates) may
generally be considered as fossilised sponges or alcyonian zoophytes,
since not only are their external forms and their superficial markings
often highly characteristic of those organisms, but when sections of
them are made sufficiently thin to be transparent, a spongy texture may
be most distinctly recognised in their interior."
[Illustration: FIG. 30.--TERTIARY FORMATION.]
During the deposition of these secondary strata in the hollows of the
surface, but little alteration of the relative situations of sea and
land could have taken place, as the deposits for the most part lie
conformably to the same hollows or "basins" (fig. 30 will illustrate
this); but after the deposition of these strata, there appears to have
been a very great disturbance, many chains of mountains were cast up
(as the Apennines), carrying upwards with them these deposits; some of
the strata were so displaced that they were left in a perpendicular
position, as may be seen in several places at the south side of
the Isle of Wight. These disturbances, however, did not amount to
so general a convulsion as those before described, nor is it known
whether all the effects produced on these strata took place at or near
the same period of time; they nevertheless appear to have produced
an almost total change in the situation of the land and sea, for the
"downs" of chalk (on the southern coast of England, for example)
were, before these changes, the beds of seas. This is the last of
the great convulsions which the earth has undergone, for the tertiary
strata which afterwards began to be deposited rest in the hollows or
basins (chiefly in the chalk) then left; the alterations in and since
these deposits appear to consist chiefly of the upheaval of certain
localities, the depression of others, the evaporation of inland lakes,
and the wear and tear of the land from these causes, which are still in
continuous action (as from the washing down of cliffs by the sea, and
the formation of mud deposits at the mouths of rivers), or the volcanic
agencies which in some places (as in Ireland) have cast up basalt over
the chalk.
The tertiary strata contain remains of most of the classes of animals
now in existence, but yet differing greatly in species, and as the
strata approach the surface those species become more and more general;
the plants also approach more nearly to those of the present time, but
still most parts of Europe possessed a climate almost tropical. The
tertiary strata consist chiefly of marine and fresh water deposits in
the form of sands and clays, as the "London clay," which extends under
London, resting upon a basin of chalk. The last deposits, forming the
superficial layer of earth, and the formation last deposited before
the creation of man, are called the Diluvium and Alluvium, and contain
numerous remains of mammalia, birds, reptiles, and fishes. One of the
most extraordinary animals of this period was the Dinotherium, a sort
of walrus, which is supposed to have been the largest of quadrupeds,
if indeed it was one (fig. 31). The quadrupeds of this, the "Pliocene"
formation, are thus described by Professor Owen in his "History of
British Fossil Mammals."
[Illustration: FIG. 31.--SKULL OF THE DINOTHERIUM.]
[Illustration: FIG. 32.--MAMMOTH, TELEOSAURUS, AND GLYPTODON.]
"At the period indicated by these superficial stratified and
unstratified deposits the Mastodon had probably disappeared from
England, but gigantic elephants (fig. 32), nearly twice the bulk of the
largest individuals that now exist in Ceylon and Africa, roamed here
in herds, if one may judge from the abundance of their remains. Two
horned rhinoceros, of at least two species, forced their way through
the ancient forests or wallowed in the swamps. The lakes and rivers
were tenanted by hippopotami, as bulky and with as formidable tusks
as those of Africa. Three kinds of wild oxen, two of which were of
colossal size and strength, and one of them maned and villous like
the bonassus, found subsistence on the plains. Deer as gigantic, in
proportion to existing species, were the contemporaries of the old
_Uri_ and _Bisontes_, and may have disputed with them the pasturage of
that ancient land. One of these extinct deer is well known as the Irish
elk, by the enormous expanse of its broad-palmed antlers (fig. 33).
Another herd proves more like those of the wapiti, but surpassed that
great Canadian deer in bulk. A third extinct species more resembled the
Indian _Hippelaphus_, and with these were associated the red-deer,
the rein-deer, the roebuck, and the goat. A wild horse, a wild ass or
quagga, and the wild boar, entered also into the series of British
pliocene hoofed animals. The carnivora, organised to enjoy a life of
rapine at the expense of the vegetable feeders, to restrain their undue
increase and abridge the pangs of the maimed and sickly, were duly
adjusted in size and ferocity to the fell task assigned them in the
organic economy of the pre-adamite world. Besides a British tiger, of
larger size and with proportionately longer paws than that of Bengal,
there existed a stronger feline animal (Machairodus) of equal size,
which from the great length and sharpness of its sabre-shaped canines,
was probably the most ferocious and destructive of its peculiarly
carnivorous family. Of the smaller felines, we recognise the remains of
a leopard, a large lynx, and of a wild cat. Troops of hyenas, larger
than the Crocuta of South Africa, which they most resembled, craunched
the bones of the carcases relinquished by the nobler beasts of prey,
and doubtless often themselves waged the war of destruction on the
feebler quadrupeds.
[Illustration: FIG. 33.--IRISH ELK. THE PALEOTHERIUM.]
"A savage bear, surpassing the _Ursus ferox_ of the Rocky Mountains,
found its hiding-place, like the hyæna, in many of the existing
limestone caverns of England. With the _Ursus spoelus_ was associated
another bear, more like the common European species, but larger than
the present individuals of the _Ursus Arctas_. Wolves and foxes, the
badger, the otter, the foumart, and the stoat, complete the category of
known pliocene carnivora of Britain."
In the time of these the last of the tertiary strata, there appear
evidences of a degree of cold much greater than at present exists;
this seems to be pretty well proved by the "boulder formation," or
prevalence of erratic blocks of stone, the progress of which have been
traced from their sources of origin to hundreds of miles distant, and
there is no conceivable power which could have carried them but the
floating fields of ice or glaciers; both of these sources are capable
of this removal, for it is not uncommon to find large pieces of rock
and layers of gravel floating on masses of ice. Glaciers are formed
by the snow on the sides of mountains becoming hardened by being
partially melted and again frozen, and at every melting the fluid tends
to descend, when it again becomes frozen, always adding to the lower
part and carrying away from the upper. In this way whole glaciers of
many miles extent become unfixed, and as fresh snows are added to their
upper parts, they descend slowly, entangling with them and tearing away
the rocks in their vicinity. When they arrive at the sea and float
forth, these rocks are borne with them.
But there are as yet no traces of man, not one small fragment of his
skeleton, not one minute relic of his constructive powers, although
the bones of man are as capable of preservation as those of any other
animal, being the same in structure and composition; the remains of
hundreds of fragile insects, seeds, leaves, and all sorts of organic
structures, are found perfectly preserved (fig. 34). The only way,
therefore, of accounting for the absence of any organic remains of man,
is the assumption that he was not then created; and this is confirmed
by the fact that in the very uppermost layers of the earth's surface
his bones and the works of his hands are found in great abundance;
it is therefore with good reason that we come to the conclusion,
that he was the last creature formed by his Maker. That the creation
of man was pre-intended by God, seems also almost proved by the
numerous objects before created, capable of ministering to his use
and happiness--capable of exercising his constructive and inquiring
capabilities--suitable to his imagination and tastes, and his only,
and which would serve no purpose of utility to the mere brutes. Of
what use, to any creature but man, is coal--of what use the metals?
Of what avail is it to any of the lower animals, that God has caused
glass and other transparent substances to have the power of refracting
the rays of light? but without which not one-half of our knowledge of
His wondrous works would ever have been obtained, for it is upon this
property alone that the powers of the telescope and microscope depend.
Of what use to any but man are fire, artificial light, and galvanism?
and yet all these were created long before man was.
[Illustration: FIG. 34--FOSSIL LEAVES.]
[Illustration: FIG. 35.--SCULPTURE FROM NINEVEH.]
It has often been asked, What does man gain by the study of the
sciences? Besides the enlarged views which they give him of his
Creator's goodness and power, they at this time are fast reaching
towards the demonstration of many obscure passages of His Holy Word as
revealed to us in the Scriptures. The study of truth can moreover never
lead one into error, and a habit of drawing correct conclusions from
the facts presented is useful to every one. Geology has confirmed one
great truth in Scripture, and overthrown the greatest groundwork of
Deism, for it had been asserted by many that man (and indeed all other
creatures) had risen to his present state by slow developments, and no
proof to the contrary had ever been given. But geology has shown that
at a certain era man was created, that (as is stated in Scripture) he
was the last of God's works, and that neither before that time had
he existed in an undeveloped form, nor since has he altered one jot
from his original configuration; and the same may be said of all other
creatures, whatever may be pretended to the contrary, for from the
sculptures brought from the ruins of Nineveh (at least 3000 years old),
there appears the same external form (fig. 35), both of man and what
animals are there depicted, and his and their habits were described by
the very earliest writers to be then as now. But with respect to the
form of the earth's surface it is otherwise, there being a slow but
continuous change. Those parts of the land exposed to the tides and
action of the waves, are washed away, and the rivers are constantly
bringing down soil to deposit it at their mouths, forming those tracts
of land known as "deltas;" every wind that blows takes away some dust
from the higher and deposits it on the lower parts of the earth's
surface, so that, to use the words of the Prophet Isaiah, "every valley
shall be exalted and every mountain and hill shall be made low." But
this alteration is so slow that it takes hundreds of years to make but
a small difference, yet a difference there undoubtedly is, and a time
must come when the alteration will be such as has been shown to have
taken place in far-back times and recorded in the strata in evident
language, for though the changes are slow the result is inevitable.
It has been ascertained that the northern part of Sweden has been
steadily rising and the southern part sinking to a corresponding
degree for many centuries past, and that the west coast of Italy has
been elevated for ages past, at the rate of not quite an inch yearly.
Volcanic actions are raising some lands and depressing others (in the
earthquakes of 1822 and 1835, the whole of Chili from the Andes to the
sea, and probably the bed of the sea to an unknown extent, was elevated
considerably), rain and the rivers carry away land into the sea, the
beds of many seas are being filled up by coral polypes and protophytes,
so that the beds of these seas must ultimately be the land whilst the
lower parts of the land will become sea.
After these various changes upon the surface of the earth, from a
climate hot beyond anything now existing, from a surface rocky and full
of fissures and inequalities, studded with islands and continents,
abounding in marshes and swamps--from a state of atmosphere in which
the higher animals could not live--to the present division and
separation of land and water, of oceans and seas, of islands and
continents, well supplied with rivers to drain off the superfluous
fluid and supply highways easy to traverse in boat or canoe, the world
remains, a fitting habitation for the creatures God has placed upon it
on every hand. Forests to shelter the wild animals from the rains and
heat of the sun; waters for those who dwell or delight in them; metals,
stone, earth, and wood for man to exercise his ingenuity upon, and
other innumerable things contributing to his comfort or luxury--all
freely given by the hand of his Heavenly Father for his well-being and
delight, that he may lack no excuse to worship and adore Him, and this
delightful earth, as Milton says:--
Brought forth the tender grass, whose verdure clad
Her universal face with pleasant green,
Then herbs of every leaf, that sudden flower'd
Opening their various colours, and made gay
Her bosom smelling sweet: and these scarce blown,
Forth flourish'd thick the clustering vine, forth crept
The swelling gourd, up stood the corny reed
Embattled in her field, and the humble shrub,
And bush with frizzled hair implicit: last
Rose as in dance the stately trees, and spread
Their branches hung with copious fruit, or gemmed
Their blossoms; with high woods the hills were crowned.
With tufts the valleys, and each fountain side,
With borders, long the rivers: that earth now
Seem'd like to heaven, a seat where gods might dwell
Or wander with delight, and love to haunt
Her sacred shades.
After all these various elevations and depressions, the land remains
at this present time in the form of large tracts occupying about a
third of the superficial area of our globe. The largest tract is made
up of Europe, Asia, and Africa, which constitute one continuous area,
Africa being almost severed from the others, but still united by the
Isthmus of Suez; the tract next in size to this is made up of North and
South America, these again are nearly severed, but still united by the
Isthmus of Panama or Darien; next come Australia and Greenland, but
these, although very large, are yet not to be compared in size with
the former two; there are numerous other large islands, as Borneo, New
Guinea, New Zealand, Madagascar, Iceland, England, Ireland, &c., and
scores of smaller ones.
The temperature of the earth (as a general rule) is greatest on the
equator and diminishes gradually towards each pole, but this is by
no means invariable, for two places of the same latitude may be
very different in climate, and a system of lines passing round the
earth from east to west, would each pass through regions of various
temperatures, or what is the same thing, lines made to follow the same
temperature would have to make various curves and contortions; such
lines have been constructed and are called "isothermal" lines. The
causes of this are to be found in the various currents of the ocean,
the tides and winds, and in the proximity to the ocean of snow-clad
mountains and arid plains. The variation of latitude in these lines
sometimes reaches as much as seven degrees.
Europe contains about 3,900,000 square miles of surface, and is
separated from Asia by the Caucasus, Caspian Sea, River Ural, and
Uralian Mountains. It is about 3000 miles long and 2400 broad, about
two-thirds being plain and table-land and one-third mountain land. The
chief mountain ranges are those which run through Norway and Sweden in
a north-westerly direction, and the mountain system along the south
part from Portugal to Turkey. This last includes the Pyrenees, which
runs from the Bay of Biscay to the Mediterranean, the highest peak of
which is Mont Maladeta (11,500 feet); the Alps, the highest point of
which is Mont Blanc (15,748 feet); the Apennines, the highest point of
which is Mont Viso (12,586 feet); the Carpathian Mountains, extending
from Presburg in Hungary towards the sources of the Waag and March, the
highest point being Mont Lemnitz (7962 feet); and the Balkan range,
which may be considered a continuation of the Alps eastward, runs as
far as the Black Sea, together with many inferior ranges and branches.
The climate of Europe embraces a range from the temperate to extreme
cold. It is bounded by the Arctic Ocean on the north, Asia eastward,
the Mediterranean Sea southward, and the Atlantic Ocean to the
westward; it contains two great inland seas, the Black Sea and the
Caspian Sea. There are three great volcanoes in Europe, Hecla,
Vesuvius, and Etna, but the plains of Auvergne contain many which are
extinct.
Asia contains the highest mountains and the most extensive table-lands
in the world. It is somewhat square, being bounded northwards by the
Arctic Ocean, westward by Europe, southward by the Indian Ocean, and
eastward by the North Pacific, and contains about 17,500,000 square
miles; the greater part is made up of two extensive tracts of elevated
land called table-lands, although these are often varied by valleys and
mountain chains of great extent, yet as a whole, they are from 5000 to
10,000 feet above the level of the sea. The eastern table-land is that
of Thibet and the Great Desert Gobi, and the western that of Persia.
Asia contains many great mountain chains, the chief of which are the
Himalaya Mountains, which run along the centre of its southern part
and contain some of the highest peaks in the world; the Dhawalagiri is
28,072 feet high, but there are some others supposed to be as high.
The Altai or Gold Mountains, forming a boundary to the lowlands of
Siberia, the highest peak of which is called the Katunia Pillars, and
is 11,000 feet high.
The Thain-schan or Celestial Mountains, the Kuen Lun, and the Hindoo
Coosh, all of which run pretty nearly east and west, while the ranges
called Uralian, Bolor, Khingan, and Chinese chains run nearly north and
south.
Africa is somewhat triangular, with its base towards Asia and its apex
pointing southward. It is bounded northwards by the Mediterranean
Sea, and at its east side by the Red Sea and Indian Ocean, while the
Atlantic flows on its south-west side. In Africa is the largest desert
in the world, the Great Desert of Sahara; it occupies nearly all the
northern part, the southern has but few mountains of great extent, but
from their elevation and the amount of waters brought down by rivers,
it is supposed that the centre has very high table lands. At the
north-western part is an extensive mountain system (the Atlas) covering
with its branches nearly 500,000 square miles, and sending its slopes
to bound the great Desert northwards.
The great tract of land comprising North and South America extends in
a longitudinal direction pretty nearly north and south through 130
degrees of latitude, or nearly 8000 miles. This great tract is divided
by a narrow neck of land (the Isthmus of Panama) into two pretty equal
portions; the northern part is peculiar, from containing a number
of lakes of immense extent, deserving well the name of inland seas,
and both northern and southern divisions for the great number and
extent of their water-courses. The whole of this great tract of land
is traversed from end to end by an extensive chain of mountains, the
longest in the world; at its southern part it forms the Andes, from
which a range is continued through the Isthmus, and onwards to form the
Rocky Mountains. In the southern division this immense chain passes on
the west side of the land close to the sea, is of great elevation in
some parts, has some of the highest mountain peaks in the world, and
volcanoes also, the highest being in the Andes (Popocatapetl is about
16,000 feet high); but from the western side of the continent the land
descends gradually to the eastern. In South America are some of the
highest table-lands known, great elevated tracts in connection with the
mountain ranges.
Australia in its interior is but little known, but the whole aspect of
the island appears to be flat, and to have but little elevation, while
Greenland and the great tracts of the northern regions beyond, deserve
more the name of glaciers, being almost entirely a mass of barren rocks
and snow.
The water-courses of these various great tracts of land are all
determined by the formation of the surface, but the amount of water
which is carried into the oceans by the rivers of any district is
always in proportion to the amount of vegetation in that district; thus
in Europe, Asia, and America, the number and extent of these correspond
with the great fertility of the soil, while the northern and western
part of Africa--the Great Desert--give off scarcely any of adequate
extent, the Nile appearing to receive its supply from the central parts
further south. The reason of it is this: wherever there is vegetation,
either in the form of grassy prairies or forests, there is also a great
reduction of temperature from the radiation and evaporation, and the
consequent formation of rain, dew, or snow, which falling on the ground
produces streams, &c.
Excepting the great tracts of land named, and islands too numerous to
be mentioned, the whole surface of the earth is covered with water,
the great divisions of which (called Oceans) are, the Arctic Ocean, to
the north of Europe, the Atlantic, between America, Europe, and Africa,
the Pacific between Asia and America, and the Indian Ocean between
Africa and Australia.
The foregoing is a very bare outline of the land and water covering the
surface; it may suffice, however, to call to mind the main features
of the earth as it is now disposed. There can be little doubt that
the great variety of climate, whether hot or cold, moist or dry, is
one of the greatest sources of happiness that can be well imagined;
it stimulates to research, travel, and inquiry into the works of God;
every change experienced tends to make man search for further change,
every new scene makes him compare it with others; and the acquirement
of a knowledge of places, and a general idea of the whole world,
expands his mind enables him to appreciate the good gifts he has
received, and affords a source of satisfaction beyond almost any other
kind of enjoyment.
THE WATERS.
[Illustration: SEA-COAST.]
How grand is the ever-moving ocean! how majestic its voice, how
terrible its anger! how beautiful every colour that is reflected from
its dancing spray, and how balmy the air which is wafted from its bosom
to refresh the heated earth, which, under the glare of a summer's
sun, seems parched with thirst. How refreshing to the senses is the
change from the dry heated grass on a midsummer day--from the dusty
roads--from the smoke begrimed town, smelling of dirt, and heated
by the reflection of the sun's rays from bricks and stones till it
becomes a furnace--from the close dark habitations of the city--from
the rattle, excitement, and continual noise of vehicles and human
voices--from the corroding cares and depressing influences attending
the fierce "battle of life"--to the cool and gentle breeze, "the wide
o'er-arching canopy of heaven," the murmur and ripple of the sea, to
the clear and exhilarating air, free from soot and laden with the odour
of the ocean--Oh what a desirable change! all human nature seems to
own it, and hasten to the shores of the great watery world, that they
may contemplate one of the greatest and grandest of God's works with
admiration and thankfulness, and be re-animated by its health-giving
powers.
It is a wonderful sight, and one which fills our minds with reflection;
here we see many of the laws of nature exemplified on a great scale.
The laws of gravity keep the surface of the ocean perfectly spherical
as a whole, while those of equilibrium keep it in constant and
ever-varying motion, the laws of attraction produce the tides, and
those of reflection and refraction cause its surface to assume all
sorts of colours and tints.
"Great art thou, Ocean, and unknown
The creatures springing into life from thee,
Earth's farthest shores full proudly thou dost own,
The cradle of thy wave from iced to torrid zone."
The ocean is full of life, both vegetative and animal; myriads of
both classes have their natural habitation in the sea, and the shore
is often, after a gale, strewed with curiosities well worth the
contemplation of those who devote their minds to thought. How many
varieties of sea-weed have you gathered? perhaps twenty; not three of
them are sea-weed at all! they are living animals, either zoophytes or
molluscs, every branch of that "_flustra_" contains a thousand living
beings, every spray of "_sertularia_" as many more, that other piece
is the "_bugula neretina_" and also owns a colony of animals: the next
is indeed a member of the vegetable kingdom, its beautiful crimson
colour makes it a conspicuous object, and there are many specimens of
the same plant, but of all shades of red, crimson, and purple, it
is the "_plocamium coccineum_." And thus it is with every object we
view, a knowledge of it brings us to respect and admire it more and
more as that knowledge increases, and none more so than some of the
productions of the sea. It is here we find specimens of the star-fish,
the sea-urchin, and other radiata. Shells of all kinds--both living and
dead--belonging to the various tribes of mollusca; crabs, shrimps, and
other crustaceans, besides the endless varieties of pebbles and other
specimens of worn-down rock, the effects of constant attrition.
If we turn from the shore and gaze upon the horizon, what a marvellous
object it is--ever receding as we recede, ever rising as we rise, and
never nearer nor farther away. This rising of the horizon, so as to be
always opposite to our eyes, is because the higher we are up the more
we see. On looking at the horizon we do not look on a perfect level,
(if we did, being above it, of course we could not see it at all)
but the depression of the line of vision is so slight as to be quite
unable to be appreciated; yet, small as it is, it enables us to see a
considerable space of the ocean, and the higher we rise--at the same
angle--the more we see. The edge of the horizon also appears curved,
being higher in front of us than on either side. This is only so in
appearance, for if any one were to place a piece of string (stretched
tightly between the hands) before his eyes, and bring it up till it is
on a level with the horizon, he would soon see that the string and the
horizon were both perfectly straight and exactly corresponding with
each other.
From the horizon we turn round and look at the chalk cliffs, those
white walls from which our native isle has received the name of
"Albion." How were they produced? by the constant lashing of the
restless waters, which are constantly wearing them away; but they are
beautiful objects, full of marvels and records of bygone ages, when
their tops were at the bottom of the deep seas.
The sea is a general name given to all the greater collections of water
throughout the world, although, in a restricted sense, it is applied
to those tracts of water of a secondary size, as the Black Sea, the
Baltic, and the Mediterranean, the term "ocean" being applied to the
larger tracts of water, as the Atlantic Ocean, the Pacific Ocean, &c.
All the great oceans and seas unite, and, in reality, form one great
world of waters, spread out and covering all the lower parts of the
earth, the term "lake" being applied to collections of water surrounded
by land, although the Caspian Sea retains the name of sea, and some of
the great lakes of America may well deserve such a name.
The waters of the sea fill up all the lower parts of the earth, so
that, almost without exception, the land is higher than the water, and
as the land in some places rises but a few feet, and in others as many
thousands, so, beneath the sea, the land sinks in many places but a few
feet, and in others perhaps as many thousands as it is known to rise
above it. The sea always maintains the same general level, although in
past ages the land has risen and fallen, sometimes in one place and
sometimes in another; indeed, the same process is taking place every
day, but in so slow a manner that centuries are required to make any
great alteration; while some tracts of land are being encroached on
by the action of the waves, others are being added to and elevated by
accumulations of mud and sand, or raised by the action of earthquakes
and volcanoes, which throw up under the sea, as well as on the land,
vast quantities of melted earth or lava, forming strata known to
geologists as basalt, tufa, &c., or eject showers of ashes and dust in
such prodigious quantities as to cover many hundred square miles of the
earth's surface. It was by one of these showers of ashes from Vesuvius
that the cities of Herculaneum and Pompeii were buried. So that, as a
whole, although the sea is continually altering slowly its position,
yet it pretty equally maintains the same elevation. At first thought it
may be supposed that the rivers constantly flowing into the sea would
alter its level, for some are so large that millions of tons of water
are brought by them into the sea every hour, and there are thousands
of rivers and rills which, night and day, pour in their tribute of
waters; but God has wisely and kindly arranged these things (like all
others) so that they shall afford us innumerable comforts, and yet
not raise up the sea so that it shall cover the land, for it requires
but a moment's consideration to be convinced that all this water which
flows into the sea must first have been abstracted from it, and it is
in this way--when the winds blow over the sea, they absorb or take up a
certain quantity of the vapour which continually rises from it; for air
absorbs a certain quantity, and a certain quantity only, of the vapour
of water; but this quantity is determined by certain circumstances,
for instance, the warmer the air, the more it will absorb, the less
the pressure on the air, the more it will absorb, and the drier the
air, the more it will absorb, that is, the less moisture it has already
got, the more will be required to make up that quantity which the other
circumstances permit it to contain. Now, what takes place if a warm,
dry, light current of wind blows over the sea, landward? Why, all the
vapour given off by the sea, to the amount of millions of gallons, is
absorbed and carried inland by the wind or current of the air, and this
continues onward, laden with moisture, until it meets with one of the
several circumstances which shall cause it to be incapable of holding
the quantity of moisture which it has already got; for instance, it
meets with another current of air colder than itself, these mingle,
the vapour of water is condensed by the cold, and a cloud is formed.
This consists of minute particles of water suspended in--not absorbed
by--air; these particles gradually collect, and down falls the rain
on to the earth. This drains off from the surface, forming rills,
which collect as they descend, by their own weight, into the lowest
channels of the ground, and form into streams and rivers, and back
into the sea comes the water which the air had taken away, with this
difference, that it is free from salt and fit for the many uses to
which fresh water alone can be applied; when the vapour rises from the
sea, none of the saline matters rise with it, for, although the water
is volatile, yet they are not, and this is the whole source of fresh
water. It is distilled in the great laboratory of Nature, and gives
nourishment to all the living beings who dwell on the land and in the
rivers and lakes; or the rain may sink into the earth and be carried
for miles and miles under ground, running through some porous stratum,
such as gravel, until it flows out in the form of a spring, bubbling up
amongst flowers and weeds, and forming the source of some river, which
receiving the rain and all the springs in the country through which it
flows, finds its way back into the ocean at last.
[Illustration: MOUNTAIN STREAM.]
This is the way in which all rivers and streams are formed. An enormous
extent of land thus drained gives rise to thousands of rills, which
collect into streams of goodly size, meandering through valleys and
pouring their tribute of waters into a main stream, which at last
accumulates by additions to its course, and becomes one of those great
water-courses which form the highway through a continent. The Amazon,
Hoang-Ho, Ganges, Nile, Danube, and Volga, may be cited as some of
the greatest water-courses and highways of civilisation. These great
rivers are navigable for large ships, even for many hundreds of miles,
and it is most fortunate that this navigation is so seldom impeded
by falls; for these, although among the grandest and most beautiful
objects of nature, yet put a stop to the navigation of a river which
would otherwise be passable for hundreds of miles further. Rivers
which run through districts subject to periodical rains, or those
whose sources lead from mountain slopes where vast quantities of snow
are deposited in winter which melts on the approach of summer, are at
such seasons of the year suddenly augmented, and generally overflow
the banks and inundate the country for miles. This is in many cases a
very great misfortune, as it spoils the land, reducing it to a swamp,
but not in every case; the overflowing of the Nile brings down with
it a great quantity of fertilising vegetable matter, and serves to
manure the whole district, for the soil being extremely porous and the
heat great, the moisture is soon got rid of, and hence it was a custom
of the Egyptians to celebrate the rising of the Nile by feasts and
ceremonies.
Lakes are formed in the same way as rivers, but, being surrounded by
high land, have no outlet for the waters so that they may flow back
into the sea. If a lake were about to be formed it would be in this
way--the rain descending on the surrounding high lands would run in
rills to the lowest part, and there collect, forming a pool which would
gradually increase in size as the water flowed into it, this increase
continuing until the surface became so large that the evaporation from
it exactly equalled the supply, it would then extend no further, but
remain a permanent lake or inland sea, giving off vapour to refresh the
surrounding country, and again receiving it back by streams and rivers,
as does the ocean.
There is scarcely a spot known on the surface of the earth, which does
not show strong evidence of having, at some former period, been the
bed or bottom of some sea or lake. Some of these evidences may be seen
in the strata or layers of earth forming the sides of the cliffs which
abut on the sea-shore, and which could not have been produced by any
other agency; these strata contain so many marine shells and other
matters peculiar to the sea, that the fact does not admit of doubt that
they were there produced. These same strata are met with throughout
the land; in sinking wells and mines, the same strata are cut through,
and have a known and uniform succession, with but few exceptions; the
cliffs, however, are the most convenient places to see these strata.
That the same process of alteration in the position of the water and
land is still going forward, is shown by many evidences, such as towns
which were once on the sea-shore, being now some distance from it, as
the City of Norwich, and in other cases the reverse. The chalk cliffs
at Dover, Ramsgate, &c., show the action of the sea in the corroded
state they present, and slips or falls of great masses which have been
undermined by the sea, are frequently occurring.
[Illustration: CLIFFS, SHOWING STRATA.]
The ancient town of Ravenspurn, at which Henry IV. landed, has entirely
disappeared, and others, recorded to have been situated on the shore,
have now only their names left. The parts of the shore most rapidly
corroded by the sea, are those composed of sand, chalk, and clay,
while those composed of the harder kinds of sandstone or of granite,
have been but little wasted away, so that they project and form the
headlands, while in many cases deposits of mud have extended them.
There are many other causes which determine the elevation or depression
of the land, besides the action of the sea and earthquakes, such as
winds, frosts, &c.
[Illustration: CHALK CLIFFS, DOVER.]
[Illustration: GREAT WAVES AT SEA.]
[Illustration: DEAD CALM.]
The slightest movement of the air communicates motion to the surface of
such a great sheet of water as the sea, and this motion is gradually
increased till one ripple meets another, and the power of both goes
to form the next, so that they acquire a very considerable size;
when a gale of wind blows, the rolling of the waves far out at sea
becomes terrific, and they rise like mountains, chasing one another
over the wide ocean. But sailors rather like a smart breeze, and more
especially did they a few years ago, when the wind was all they had
to depend upon for onward progress. In those days a calm which would
sometimes last for weeks together was to them most fearful, for it was
often a source of great distress and privation, especially if short of
provisions; the sea would then look like a great pool of stagnant water
covered on the surface with sea-weed and animalculæ, and fearful it
must have been when food was failing, and no hope of progressing but
the springing-up of a wind. But, in these days, with the assistance
of steam, a calm is the very time in which most progress is made,
and there is no doubt but a time will come when it will be matter of
wonder that men could ever have trusted to so uncertain an element as
the wind; yet, if it were not for the winds, currents, and tides, the
sea could not maintain its state of purity, for its saltness is not
sufficient to prevent the growth of fungi and all sorts of animalculæ,
which, from their decay, would produce noxious gases and be most
injurious to animal life. Its constant motion alone prevents this,
and the spores and germs are tossed about until destroyed and eaten
up by the inhabitants of the deep who devour every kind of organic
matter which is deposited in the sea, and thus it is that the waters
of the ocean are so bright and clear that an object can be seen at a
considerable depth.
That the constant currents of the sea prevent the formation and growth
of sea-weed, is clearly shown by the great "Sargasso Sea," or tract of
weed (_Fucus natans_), called the Gulf-weed. This great tract embraces
thousands of square miles, and is situated in the very middle of the
Atlantic Ocean, where there are but few currents; but surrounding it
is the Gulf-Stream, an enormous current of water running at a regular
rate of four or five miles an hour. This Gulf-Stream is supposed to be
caused by the same laws and influences which determine the trade-winds,
namely, a constant rarefaction of the water at the tropical parts of
the earth, and a corresponding condensation at the Arctic portions,
for warm water is much lighter than cold, and when the waters of the
tropical regions become lighter the heavier waters of the cold regions
pressing down more forcibly tend to raise them above their proper
level; they therefore flow towards those very parts which have sunk
down by their contraction, and a constant current takes place--this
current is the Gulf-Stream. It runs from the Gulf of Mexico northwards
towards Newfoundland, turning by Iceland towards the British Isles, by
France and Spain, onwards to the coasts of Africa and South America,
the West Indies, and again to the Gulf of Mexico, although the return
current does not go by the name of Gulf-Stream. This great stream of
water warmed by the tropical sun serves the same two purposes described
under the section "Air" as being fulfilled by the trade-winds,
namely, a circulation and distribution of the superfluous heat of the
equatorial regions, warming the northern countries and cooling by the
return of under-currents those in the tropics. The fogs of Newfoundland
are caused by the great current of warm water entering the cold region
and carrying with them surface-currents of moist air, which the cold
condenses into fog, just as the breath is visible in a cold atmosphere.
England owes its moist and mild climate to the same cause.
The sand which lies upon the sea-shore is produced by the action of the
waves constantly dashing against the earth and rocks of the coast, and
is mostly composed of what chemists call "silex," or silica, which is
a chief constituent of most rocks and earths; these, being worn down
by the action of the waters, form sand. The fragments of these rocks
(especially granite) and those which contain silica in the form of
minute crystals, are soon rolled and rubbed together until they are
ground to powder, but it is doubtful whether any sand exists at the
bottom of the deep seas far from shore, as the waters there lie--and
must have laid--perfectly quiet ever since they were seas, for the
greatest storm that ever rages does not affect the tranquility of
the sea more than a few fathoms beneath its surface, so that a stone
dropped in the middle of the Atlantic Ocean, could be picked up after
a hundred years exactly where it fell, were it possible for any to
find out the spot and descend; but the bottom of some deep seas, as in
the antarctic regions and the north Atlantic Ocean (as the soundings
between Ireland and America have lately shown), is covered to an
unknown depth with what had been supposed to be sand, but which is not
sand at all, but a wonderful collection of minute shells and coralines,
which to the unassisted eye have the appearance of sand. They are
the silicious shells and coverings of minute vegetables and animals,
these creatures, being coated with silica (a substance indestructible
by age and the action of water), fall to the bottom of the sea and
there accumulate in such countless myriads that they form this fine
substance, long mistaken for sand, but between which, in reality, there
is a marked distinction, the one being formed by the disintegration and
grinding-up of rocks, the other the product of organic life; this, when
it has accumulated for ages, will, in all probability, form some island
or part of a continent, and be the site perhaps of some magnificent
city, reared upon a foundation of these minute wonders of the deep,
whose skeletons will have become consolidated into a hard and compact
stone, of which its houses and churches will, in all probability, be
built.
This is not imagination, as such occurrences have really taken
place--all our chalk cliffs and downs constitute part of an immense
stratum. Now, every grain of this chalk contains and is made up of
thousands of minute shells and corals. These chalk downs were once the
bed of some ocean which, in all probability, was filled up by their
remains.
What are the railroads and works of men's hands compared with this? Of
this chalk (hardened by pressure into limestone) most of our public
buildings are constructed, or (changed by pressure and heat into
marble) our statues of great men have been carved. What a mockery to
choose marble as the medium of rendering our heroes immortal--itself
the very type of mortality, being formed by the death of millions of
creatures.
In Dr. Carpenter's work on the microscope occurs the following:--
"Thus, when we meet with an extensive stratum of fossilised
_Diatomaceæ_, in what is now dry land, we can entertain no doubt that
this silicious deposit originally accumulated either at the bottom of
a fresh-water lake or beneath the waters of the ocean, just as some
deposits are formed at the present time, by the production and death of
successive generations of these bodies, whose indestructible casings
accumulate in the lapse of ages, so as to form layers, whose thickness
is only limited by the time during which this process has been in
action.
"In like manner, when we meet with a limestone rock entirely composed
of the calcareous shells of Foraminifera--some of them entire,
others broken up into minute particles--we interpret the phenomenon
by the fact that the dredgings obtained from certain parts of
the ocean-bottom, consist almost entirely of remains of existing
Foraminifera, in which entire shells--the animals of which may be yet
alive--are mingled with the debris of others that have been reduced by
the action of the waves to a fragmentary state.
"Now, in the fine white mud which is brought up from almost every part
of the sea-bottom of the Levant, where it forms a stratum that is
continually undergoing a slow but steady increase in thickness, the
microscopic researches of Professor Williamson have shown that not only
are there multitudes of minute remains of living organisms, both animal
and vegetable, but that it is entirely or almost wholly composed of
such remains."
[Illustration: ORGANISMS FROM MUD.]
The water of the sea is everywhere salt, except at the mouths of
great rivers, where the quantity of fresh water displaces that which
properly belongs to the sea. The cause of its saltness is the solution
of a natural mineral (chloride of sodium) which exists in the earth
in great abundance in layers of a crystalline structure, and as this
chloride of sodium (common salt) is soluble in water, of course it is
all dissolved by the water in whatever situation they may come into
contact with each other. The composition of sea-water differs slightly
in different parts of the earth, the southern seas being slightly
more salt than the northern. As a general rule, about five per cent.
of solid matter is contained in sea-water, of this rather more than
half (5.7) is chloride of sodium; the greater part of the other half
consists of different salts of magnesia, and this is the whole source
of the medicines known as Epsom salts and magnesia, the former being
the sulphate and the latter the carbonate of magnesia. Iodine, another
article used in medicine and photography, is also extracted from
sea-water, which however contains but a very minute portion, too small
to be detected as a general rule, but extracted by burning certain
sea-weeds, in the ashes of which it is found in sufficient quantity to
be separated.
Although the sea as a whole keeps its level, yet in various parts it is
constantly rising and sinking, sometimes at one place and sometimes at
another; these risings and fallings are called tides, and are caused
by the joint action of the sun and moon, that is, by their attraction,
acting at different distances. First it must be observed (as is well
known) attraction varies inversely as the square of the distance, that
is, if the moon were twice as far off, her attraction of the earth
would be one-fourth of what it now is, if three times as far off,
one-ninth, and so on.
The moon's average distance from the centre of the earth (A to C, in
the diagram) is about 240,000 miles, or about 60 times the earth's
radius (B C), which is a little under 4000 miles, consequently if the
distance from the moon to the centre of the earth (A C) be expressed
by 60, the distance to the nearest surface (A B) will be 59, and the
farthest surface (A D) 61. The moon will attract the point B with a
force of 1/59^2 or 1/3481, the point C with the force of 1/60^2 or
1/3600, and the point D with the force of 1/61^2 or 1/3721. Now as
the force at C is greater than at D, the earth itself will be pulled
away from the water at D, and leaving it a little behind, will produce
a high tide there, this tide is known as the "inferior tide" (2).
Again as the force at B is greater than at C, the water at B will be
pulled away from the earth and produce a still higher tide, called the
"superior tide" (1), or that which takes place when the moon is due
south. This heaping-up of the waters by the moon, to the height of
4-1/2 feet (on an average) causes corresponding depressions to the same
depth in those parts of the earth which are situated between the raised
parts, making a difference between high and low-water of nine feet due
to the moon; precisely the same effects are produced by the sun, but
though his attractive power is so much greater than the moon's, his
distance is also so much greater, that the heap of water he can raise
is somewhat less than 2 feet, and makes therefore less than 4 feet
difference between high and low-water, due to the sun. When the sun
and moon are both on the same side, or on opposite sides of the earth
(as at new or full moon), then the attraction of both act together and
produce "spring tides," with a difference of 13 feet; at first and last
quarter the sun and moon oppose each other, acting in cross directions,
and the difference is then only 5 feet. But these effects could only
take place in the wide open space of an ocean, and when other forces do
not interfere, such as obstruction to the tide-waves by land, &c.
[Illustration: DIAGRAM OF THE TIDES.]
Inland seas (as large as the Mediterranean even) have but very little
tide, while pinched-up rivers may have a great rush of tide, as at
Bristol, where it rises to 45 feet sometimes, and at Anapolis in Nova
Scotia, to so much as 120 feet! Wind will also accelerate or retard
both the speed and height of the tides. London receives a much greater
tide than its due, for the tidal-wave being interrupted by Ireland and
England, rolls up the western coast (taking a northerly direction) with
such force as to swing round the Shetlands and all down the eastern
coast of Great Britain. The direct Atlantic wave also, when split by
our island, rolls along the south coast from Land's-End to Dover,
rushes through the "Straits," and meets the backward wave which has
been travelling round by Scotland (as before mentioned), the two then
pour into the Thames and give an otherwise quiet river a high and
useful tide; so that London receives two tides, the southern one nearly
10 hours after Cornwall, and the roundabout one not till nearly 23
hours after it first reaches England.
[Illustration: RIVER THAMES.]
The waters are the great highway throughout the whole world, and what
an easy transit it has formed to those nations sufficiently civilised
to require a further knowledge of the world, and thence procure for
themselves luxuries not obtainable at home--at the same time, spreading
civilisation wherever they go!
If the oceans, instead of forming one great concourse of waters, had
existed in the form of inland seas or great lakes, the great chains
of mountains, deserts, and uninhabited tracts of earth, would, in
some cases, have formed impassable barriers, whilst in other parts
civilisation would have been impeded from the easy access of the more
savage tribes, who would have despoiled the more fortunate by inroads
amongst them, mingling with or exterminating them, and checking the
onward progress of civilisation. And this has always existed where
great tracts of land are, which are the last parts of the world to be
civilised, and in many parts remain as rude as they were thousands
of years ago. All this is owing to the good and wise arrangement of
water and land, and is an instance of the care and foreknowledge of
God, who has provided for the onward progress of that creature to whom
alone such a progress has been allotted; but as they now exist the
oceans form impenetrable barriers to the savage, so as to restrict
his brute force and uncultivated habits spreading, while they form
easily-traversed highways to the more civilised nations, enabling them
to spread their civilisation without contamination to themselves, but
to the advancement of others.
The oceans are now navigated by thousands of vessels engaged in
mercantile objects, and it is perfectly astonishing with what rapidity
and safety these great tracts of water are crossed.
In one of Chambers's "Papers for the People," called "Ocean Routes," is
the following, speaking of the perfecting of the steam-vessel:--
"The regularity, speed, and safety with which the voyages of these
vessels were made, soon pointed them out as the best conveyance both
for passengers and the mails.
"In 1821 they were employed on the latter service between Dublin and
Holyhead, and between Calais and Dover; and now, with few exceptions,
all the channel and ocean-work of the Post-Office is done by steamers,
and all the passengers and much of the goods' traffic between the parts
of Great Britain and Ireland, have been within the last quarter of a
century transferred to them.
"After the steamboat had thus passed through the various stages of
infancy and childhood--had tried its strength on English rivers, in
the Irish Sea, and in the British Channel--men began to ask, was it
not strong enough and old enough to do more? Could it not cross an
ocean as well as a channel--take letters and men, and merchandise to
America, India, and Australia, as well as to Ireland and France? In
this question were involved considerations of the highest importance to
all the world, but particularly to this country, for no other country
has such extensive foreign possessions as Great Britain, or carries on
such an extensive trade.
"With the exception of the United States, all the colonies planted by
the British remain parts of the empire, while Spain and Portugal have
lost nearly all those rich territories, extending over the fairest
portion of the American continent, that at one time acknowledged the
sway of the houses of Bourbon and Braganza. The foreign possessions
of France are insignificant, and, of the other nations of Europe,
the Dutch alone possess a territory abroad greater than they have
at home.... The proud position of Britain among the nations, the
necessities of her foreign trade, and the wants of her colonies and
dependencies, apart from all other considerations, rendered it fitting
and natural that she should lead the way in maritime enterprise, and
teach the nations how to navigate the ocean by steam.
"Nor has she failed in this high task; for, within thirteen or fourteen
years, since the question was first proposed, she has established lines
of gigantic steam-vessels that are now traversing with regularity and
safety every ocean, steaming altogether more than a million and a
quarter miles every year, and distributing letters and newspapers all
over the world, at a cost to the country of about £650,000 per annum."
The rapidity and ease with which thousands of troops were lately
conveyed to the Crimea and India, together with all their stores,
horses, &c., form one of the most wonderful feats of ocean navigation
ever performed, and point out the beauty of those arrangements which
enable man to traverse the whole earth, whether by land or by water, so
that it may fairly be said that the civilisation of the world depended
and still depends upon the waters.
INTRODUCTION TO THE ORGANIC KINGDOMS OF NATURE.
The foregoing descriptions refer to the great works of God as seen in
those creations which possess not that most wonderful attribute--life.
There is no limit in extent, in quality, or in number, to these works;
their extension appears to be infinite; their magnitudes are large
or small, just as we compare them one with the other. This earth is
an enormous mass, contemplated in comparison with ourselves, but an
insignificant speck when compared with the sun, and there are certain
laws, chemical and mechanical, which govern them all--heat, light,
and electricity permeate all the infinity of space--attraction exists
everywhere. There are no individual existences among them; all are
made up of matter combined according to certain definite chemical
laws, and always obedient to them under the same conditions--moving
according to certain mechanical laws, and always obedient to them. The
Creator who made these lifeless masses made also the laws to regulate
them; but, besides these, it has pleased Him to form certain other
creatures not for an instant to be compared in size or quantity with
the former, and made up also of certain chemical compounds obedient
to the mechanical and chemical laws, with one more addition, that
unknown, inexplicable attribute--life. This wonderful quality exists
in all organic beings; they obtain by it individual identity; they are
whole creatures--imperfect with any part taken away, also imperfect
with any addition. Clay is clay, in any quality or form; iron is
iron, whether a grain or a ton; but a tree is only a tree when it
is complete. We cannot say "some tree," as we would "some clay," it
must be _a tree_, or several trees, each a separate and complete
existence--perfect in itself--made up of solids and fluids, and
possessing certain attributes, namely, a constant circulation of its
fluid parts, a constant appropriation of food and rejection of waste
matters--growth thereby to a certain definite form, and in many a
definite size, together with the production of germs, capable, under
certain conditions, of producing beings exactly similar to themselves.
This constitutes organic life, and is possessed by all vegetables.
Animal life is exactly the same, with the super-addition of will or
mind in its most perfect state, of instinct or some analogous function
in its lower states, or in quite the lowest--a chemical and mechanical
difference only, such as shall determine the choice of food and mode of
assimilating it. This difference consists in the vegetable feeding upon
inorganic food, and the animal on food which has received the stamp of
organisation. Creatures possessing life, whether vegetable or animal,
are called organisms. It is found that these organisms are made up of
certain atoms united in larger multiples than in inorganic substances,
which are either simple or compounded of but few atoms; thus water is
composed (every atom of it) of _one_ atom oxygen, united to _two_ of
hydrogen. Common salt (every atom of it) is composed of _one_ atom of
the metal sodium with _one_ atom of chlorine. Chalk is compounded of
_one_ atom of calcium in union with _one_ of oxygen, and this united to
one atom of carbonic acid, itself composed of one atom of carbon with
_two_ of oxygen. But organic compounds are often made up of four or
six elements, united in multiples of their usual combining quantities.
Thus, grape-sugar is made up (every atom of it) of 24 atoms of carbon,
28 of hydrogen and 28 of oxygen; these 78 atoms unite and form one
compound atom, of which the sugar is wholly compounded, and thus,
from such a complex nature, it happens that most organic compounds
are decomposed by even a moderate degree of heat--all by a heat equal
to red-hot iron. From these facts, it may be therefore stated, that
all organisms are complete in themselves, have definite lives or
existences, appropriate certain matters to themselves, grow thereby,
and are compounded of organic atoms.
THE VEGETABLE KINGDOM.
[Illustration]
QUANTITY, DISTRIBUTION, AND OFFICES OF THE VEGETABLE.
In contemplating nature there are few things which give more delight
than the beauty and variety of the vegetation which clothes the surface
of the earth, whether it be that we contemplate the grassy covering
of the plains of the Old World, or the immense "prairies" of the New,
spreading out as it were into seas of grass, and giving food and
shelter to thousands of wild animals; or gaze upon the rocky height of
some vast mountain range, and see the gigantic oak or pine, forming
by their wide-spread shades the solemn forest which extends for miles
beneath us, and which forms a shelter for the various tribes of birds,
monkeys, and other animals, to whom it is a home of happiness and
plenty--under every aspect the contemplation of nature's clothing fills
the mind with awe and admiration.
There is hardly anything more refreshing to the mind than the
contemplation of trees and shrubs congregated into a wood, the floor
of which is carpeted with mosses and flowers, where the gigantic and
gnarled trunks of the forest trees covered with many-coloured lichens
starting up all round, circumscribe the view, while the wide-spreading
boughs and the leafy canopy overhead exclude the sun's rays. It is here
that one views nature in her purest forms and colours, untouched by the
destroying hand of artificial arrangement.
The immense preponderance of the vegetable over the animal world in
quantity compensates somewhat for the superior organisation and the
intelligence of the latter, which must be studied in the individual,
while the vegetable world, which can be contemplated in the mass,
almost overwhelms the imagination with its vastness. It is indeed
impossible to compute the amount of vegetation in the great forests
of America and Russia (in which latter country are the largest in the
world), covering hundreds, nay thousands, of square miles with one
continuous growth of timber. That forest in Russia through which the
river Pechora flows, extends over a space of 150,000 square miles!
The whole mass of animated existence sinks into insignificance when
compared in quantity with this; and when to these forest-tracts are
added the thousands of square miles of grass and heaths which grow in
some climates with wonderful luxuriance, the amount of the vegetable
kingdom is at once placed beyond all comparison with the animal kingdom
in point of quantity. Cooper, in his American novels, describes the
prairies as great seas of grass extending as far as the eye can reach,
and rising to a height of 8 or 10 feet; and Humboldt describes some of
the grasses on the plains of the Oronoco, as being so gigantic that
they measure 18 feet from knot to knot, and says the Indians use them
for blow-pipes to shoot their poisoned arrows from. And--as though it
were not sufficient that the earth should bring forth everywhere all
kinds of trees, shrubs, and grasses--the waters of the ocean itself are
often filled with vegetable life; in some tracks the tangled sea-weed
(_Fucus Natans_) is so dense as to impede the onward progress of ships
for hundreds of miles together.
Humboldt, in his "Views of Nature," describing the two great banks
of sea-weed, says: "The two banks of sea-weed, together with the
transverse band uniting them, constitute the Sargasso Sea of the older
writers, and collectively occupy an area equal to six or seven times
that of Germany."
[Illustration: FIG. 1.--DIATOMA VULGARIS.]
[Illustration: FIG. 2.--VARIOUS DIATOMACEÆ.]
Nor is this the only vegetation which the great world of waters
contains, for if we descend from the contemplation of its larger
members we find them even surpassed in quantity by others of such
extreme smallness, that they can only be seen individually by means
of the microscope, but which exist in such prodigious quantities that
the mind can hardly realise the fact. These vegetable atoms have been
so increasing and depositing their minute coverings at the bottom
of most parts of the ocean, that for hundreds of miles their beds
are composed of nothing else, and it has been found that most of the
great changes on the surface of the earth have been effected by these
minute creatures and their companions of the animal world; for as we
find chalk-downs and coral-reefs formed by the remains of microscopic
animals, so productions of equal extent have been formed by the
smallest members of the vegetable kingdom, chiefly the "Diatomaceæ," a
race of minute vegetable productions which propagate by sub-division
and have the power of withdrawing earthy matters from the waters in
which they live, which forms a sort of shell or covering; this shell
at their death remains indestructible and gradually accumulates in
the bed of the sea (fig. 1). Examination of the various strata of the
earth shows that chains of hills, beds of marl, and almost every kind
of soil, whether superficial or raised from a depth, consist in a great
proportion of the earthy remains of these minute plants. These tracts
of land were once the beds of oceans which were thus gradually filled
up. The waters of the Antarctic Ocean are often opaque and quite brown
from the multiplicity of these creatures, the lead used on shipboard
for sounding coming up from the bottom covered with what appears to
be mud, but which on a microscopic examination proves to be nothing
else than the shells of these and allied species (fig. 2). Thus we
find the land and the waters are everywhere full of vegetable life;
the air itself moreover is so filled with the germs of vegetable and
animal creations, that it is quite impossible to exclude a portion so
small that it shall not contain any; in proof of which, any organic
substance set by for a few days in a vessel ever so carefully closed,
is shortly covered with a growth of mould consisting of fungi, which
under the microscope present most beautiful forms and colours (fig. 3).
The cause of this is a deposit from the air of the spores or germs of
these creatures, and the nature of the decomposing substance into which
they fall often determines the race or tribe which shall come to life
and inhabit it, showing plainly that but a few of these only among many
come to maturity, just as when a variety of seeds are thrown on any
particular kind of soil, only those to which the soil may be suitable
come to perfection.
[Illustration: FIG. 3.--_a_ _a_, MOULD FROM AN OLD BONE--_b_,
MOULD FROM JAM.]
Dr. Carpenter in his work on the microscope says:--"There are scarcely
any microscopic objects more beautiful than some of those forms of
mould or mildew which are so commonly found growing upon the surface
of jams and preserves, especially when they are viewed with a low
magnifying power and by reflected light; for they present themselves as
a forest of stems and branches of extremely varied and elegant forms,
loaded with fruit of singular delicacy of conformation, all glistening
brightly on a dark ground.
"The universality of the appearance of these simple forms of fungi
upon all spots favourable to their development, has given rise to the
belief that they are
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