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s large as Jupiter, the intensity of gravity at its surface would be so great that it would prevent the sap from rising in our trees, and absolutely stop the vital movements of every plant we are possessed of. Thus we may perceive a wonderful relation between the mass of the globe and the budding of a snow-drop. Further, any considerable increase of the force of gravity, beyond that which we experience at present, would be wholly subversive of the muscular powers of all our animals. The fawn would feel almost as heavy as the elephant, the hare would creep like a sloth, the tiger would lose the power of springing on his prey, and man himself, moving with difficulty and pain on his hands and feet, would be degraded to the rank of a quadruped. He could scarcely breathe, so dense would be the lower strata of the atmosphere; the felling of a single tree would cost him his life; he could not guide the plough, nor sink a well, nor raise the rocks from the bosom of Jupiter for the erection of bridges or of temples, which, if such edifices. exist there, must be upon a Cyclopean scale, in order to resist the floods and tempests of that planet. He could not live there a single day, unless his stature were strengthened with additional muscles, supplied with a new tide of the vital current, with new channels for its circulation, and a robust furniture of lungs proportioned to his powerful frame. The facility with which all our animals, from the elephant to the squirrel, execute their movements, and go through the circle of their existence, shows that their size and limbs and muscles, and the most minute instruments which are subservient throughout their structures to the maintenance of life, have been adjusted with the nicest precision to the force of gravity, which, emanating from the mass of the earth, operates upon them. So also it is with man. All over our globe he bears the same proportion to its magnitude, thereby clearly showing that the Omnipotent, in creating him, weighed him as it were in one hand while poising the earth in the other.

The invariable regularity with which the earth accomplishes its orbit is in itself a striking proof of the divine perfection with which that orbit was traced out. A difference of ten days at one time, of three weeks or a month at another, in the length of our year, would disappoint the labours of the husbandman, and render every attempt at chronology abortive. The history of past generations would be a chaos, and all calculations as to the future, with respect to astronomical phenomena, and every thing connected with time, would be altogether visionary. We could have neither months nor years-nothing but a succession of days to which we could hardly give a name—and the whole of our present routine of life would be thrown into irrecoverable confusion. The dexterity, if we may use such a phrase, with which the earth preserves

its

its path in space, without encountering any of the numerous comets which are perpetually wandering in all sorts of orbits through the firmament, is the result of a provision that must have been made before one of those enormous masses was launched upon its course. The comet of 1680 was followed by a tail which considerably exceeded in length the whole interval between the sun and the earth; the tail of the comet of 1769 extended sixteen million leagues; and that of the great comet of 1811, thirty-six millions. The orbit of the small comet called after M. Biela, of Josephstadt, by a remarkable coincidence, very nearly intersects that of the earth; and it is very well known, that had the latter been only a little month in advance of its actual place at the time of the passage of that comet in 1832, there must have been a rencontre between them. Considering that Biela's comet is so small, and, like Encke's, is scarcely more solid than a cloud, it might not possibly have produced any effect upon the orbit of the earth. But it would have most probably deranged, during its passage, the component parts of our atmosphere, rendered it very generally inconsistent with the continuance of animal life, and prodigiously aggravated the pestilence with which so many nations were visited in that fatal year.*

The mean depth of the sea is, according to La Place, from four to five miles. If the existing waters were increased only by onefourth, it would drown the earth, with the exception of some high mountains. If the volume of the ocean were augmented only by one-eighth, considerable portions of the present continents would be submerged, and the seasons would be changed all over the globe. Evaporation would be so much extended, that rains would fall continually, destroy the harvests, and fruits, and flowers, and subvert the whole economy of nature. There is perhaps nothing more beautiful in our whole system than the process by which the fields are irrigated from the skies-the rivers are fed from the mountains-and the ocean restrained within bounds, which it never can exceed so long as that process continues on the present scale. The vapour raised by the sun from the sea floats wherever it is lighter than the atmosphere; condensed, it falls upon the earth in water; or, attracted to the mountains, it gathers on their summits, dissolves, and perpetually replenishes the conduits with which,

*It is curious enough that Jupiter, whose vast magnitude, as compared with Earth, enables him to sustain such shocks with impunity, seems to be a perpetual stumblingblock to comets. The comet of 1770 actually got entangled among his satellites, and being thrown out of its orbit by his attraction was forced into a much larger ellipse than it had traversed before. It is a proof of the smallness of the mass of that comet that none even of Jupiter's satellites suffered the least perceptible derangement of motion from this extraordinary conflict. What effect it may have produced upon animal life within his atmosphere, we have no means of conjecturing.

externally

externally or internally, they are all furnished. By these conduits the fluid is conveyed to the rivers which flow on the surface of the earth, and to the springs which lie deep in its bosom, destined to supply man with a purer element. If we suppose the sea then to be considerably diminished, the Amazon and the Mississippi, those inland seas of the western world, would become inconsiderable brooks; the brooks would wholly disappear; the atmosphere would be deprived of its due proportion of humidity; all nature would assume the garb of desolation; the bird would droop on the wing-the lower animals would perish on the barren soil and man himself would wither away like the sickly grass at his feet. He must, indeed, be incorrigibly blind, or scarcely elevated in the scale of reason above the monkey, who would presume to say, or could for a moment honestly think, when duly informed on the subject, that the machinery by which the process of evaporation and condensation has been constantly carried on upon earth for so many centuries, exhibits no traces of divine science and power, and especially of benevolence towards the countless beings whose subsistence and happiness absolutely depend upon the circumstance of the waters of the ocean, earth and air, uniformly preserving the average of their present mutual proportions.

Let us glance in passing at the amount of riches which this process at present bestows annually upon mankind, particularly in those countries where they have complied with the first condition of happiness imposed on them by their Creator, that of assiduously labouring to cultivate the earth. We find that in France, which teems with an agricultural population, unskilled however in many of the modern improvements that have been carried to such perfection in Britain and Belgium, the average yearly produce is about twenty-one millions of quarters of wheat, thirtytwo millions of other grain, and sixteen of chestnuts and potatoes, the whole of which would amount, at moderate prices, to about one hundred and forty millions sterling, exclusive of the wealth which they gain by their olives and vines. The annual value of all the grain grown in Britain, and of its cattle, sheep, hides, wool, butter, cheese, and poultry, has been estimated at about two hundred and twenty millions sterling. A French writer, whose elaborate tables, though not always accurate, offer in most instances an approximation to the truth, has estimated the ordinary number of our sheep at forty-two millions, of our cattle at ten millions, and of our horses at one million eight hundred thousand. It has been calculated, that the wool shorn from our sheep in one year was worth, at eighteen pence a pound, a sum exceeding eight millions sterling. If we consider that the wines of France are but

the

the vapours drawn from the sea by the sun, returned by the clouds and mountains to the earth, thence pumped up through the stems of the vine and distributed through the purple clusters with which at the vintage-time their branches are weighed down, we must at once perceive that any material derangement of the process in question would convert all the vineyards of France into mere collections of wood, fit only to be cut down and thrown into the fire. By the same process a grain of wheat may with due care be multiplied into four or five thousand. In the Philosophical Transactions (1768, p. 203) a curious instance is stated, in which forty-seven pounds of wheat were actually obtained from one single seed. So also wool, milk, and flesh are but grass and corn changed into those substances by the assimilating system of the animal body, which could not be carried on for many days if half the waters of the sea retired into the caverns of earth. The mind is almost overwhelmed with a sense of the ever-present Deity, when we consider that at this moment there are upwards of a thousand millions of human beings walking on this globe, dependent for their daily maintenance upon the vapours of the ocean, which have never yet ceased to be raised, by the agency of the sun, in the proportions exactly requisite for the wants of man from season to season.

The atmosphere, which we cannot see, but which we feel investing us wherever we go, whose density we can measure to a certain height, whose purity is essential to existence, whose elastic pressure on the lungs, and on and around the frame, preserves man in that noble attitude which lifts his head toward the skies, and bids him seek there for an eternal home-the atmosphere, which is neither an evaporation from earth nor sea, but a separate element bound to the globe, and perpetually accompanying it in its motions round the sun-can we for an instant imagine that we are indebted for it only to 'some fortuitous accident? If there were no atmosphere, and if we could exist without one, we should not hear the most powerful artillery discharged at the distance of a single pace; we should be deprived of the music of the sea, the minstrelsy of the woods, of all the artificial combinations of sweet sounds, and of the fascinating tones of the human voice itself. We might make our wants and our feelings perceptible to each other, by signs and gesticulations, but the tongue would be condemned to irremediable silence. The deliberations of assemblies of men, from which laws and the order of society have emanated, could never have taken place. The tribes of mankind would wander over the earth in savage groups, incapable of civilization, and the only arts which they could ever know would be only those that might enable them to destroy each other.

Language

Each

Language must be spoken before it can be represented by symbols. Without an atmosphere, therefore, we should have had no records, traditional or documentary, of past ages. generation would have to depend upon its own experience, and the generations now arrived at maturity would have been no wiser than those which lived before the flood. We should have had no press, no mathematics or astronomy, no eloquence or poetry, no steam-boats, rail-roads, or manufactures. Clothed in the skins of wild beasts, we should have sought shelter in the mountains and forests, have been incapable of preserving revelation, and have never obtained from our own intelligence any idea of the rank which we fill in created being. Let any man examine the ear either of one of his fellow-men or of the lower animals, and say, whether it is not exquisitely fitted for the reception of sound, which can only be propagated through the medium of the atmosphere. Can it be doubted then that the ear was made for the atmosphere, or the atmosphere for the ear? But by whom so made? When Epicurus first read, with his preceptor, these verses of Hesiod :

Ήτοι μεν πρώτισα Χαος γενετ' αυταρ έπειτα

Γαι 'ευρύστερνος, παντων εδος ασφαλές αιτί

Αθανάτων.

Eldest of beings, Chaos first arose,

Thence Earth wide stretched, the steadfast seat of all
The Immortals,

his inquisitive spirit prompted him to put a similar question'And Chaos whence?' In his riper years the philosopher satisfied himself that Chaos arose from the fortuitous concourse of atoms, but he has forgotten to leave us an answer to the question— 'And Atoms whence?'

The atmosphere, immense as its volume is, surrounding the globe on all sides to the height of forty miles or more, is never in our way. We raise our hand and put it aside, but the fluid, from its elasticity, soon resumes its place. It diffuses and tempers the heat of different climates, circulates from the pole to the equator, sustains the clouds in an expanded form, and thus equally divides their waters over the surface of the earth, and exercises an immediate agency in the generation and direction of the winds, which tend perpetually to restore the equilibrium of genial warmth and moisture. We already know that without it the ear would be useless. If there were no atmosphere, the eye also would be comparatively inefficient; we should see nothing except objects on which the sun's rays fell directly or by reflection-dazzling the sense in either case. The atmosphere, by its refracting power, economises the separate sunbeams, melting, as it were, the lines

of

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