which is requisite for these purposes. Were it much harder than it now is; were it, for example, as dense as a rock, it would be incapable of cultivation, and vegetables could not be produced from its surface. Were it softer, it would be insufficient to support us, and we should sink at every step, like a person walking in a quagmire. Had this circumstance not been attended to in its formation, the earth would have been rendered useless as a habitable world, for all those animated beings which now traverse its surface. The exact adjustment of the solid parts of our globe to the nature and necessities of the beings which inhabit it, is, therefore, an instance and an evidence of Wisdom.

The diversity of surface which it every where presents, in the mountains and vales with which it is variegated, indicates the same benevolent contrivance and design. If the earth were divested of its mountains, and its surface every where uniformly smooth, there would be no rivers, springs, or fountains; for water can flow only from a higher to a lower place; the vegetable tribes would droop and languish; man and other animals would be deprived of what is necessary for their existence and comfort; we should be destitute of many useful stones, minerals, plants, and trees, which are now produced on the surface, and in the interior of mountains; the sea itself would become a stagnant marsh, or overflow the land; and the whole surface of nature in our terrestrial sphere would present an unvaried scene of dull uniformity. Those picturesque and subime scenes which fire the imagination of the poet, and which render mountainous districts so pleasing to the philosophic traveller, would be completely withdrawn ; and all around, when compared with such diversified landscapes, would appear as fatiguing to the eye as the vast solitudes of the Arabian deserts, or the dull monotony of the ocean. But in consequence of the admirable distribution of hills and mountains over the surface of our globe, a variety of useful and ornamental effects is produced. Their lofty summits are destined by providence to arrest the vapours which float in the regions of the air; their internal cavities form so many spacious basins for the reception of waters distilled from the clouds; they are the original sources of springs and rivers, which water and fertilize the earth; they form immense magazines, in which are deposited stones, metals, and minerals, which are of so essential service in the arts that promote the comfort of human life; they serve for the production of a vast variety of herbs and trees; they arrest the progress of storms and tempests; they afford shelter and entertainment to various animals which minister to the wants of mankind: in a word, they adorn and embellish the face of na ture-they form thousands of sublime and beau -iful landscapes, and afford from their summits no most delightful prospects of the plains below.

All these circumstances demonstrate the consum. mate wisdom of the Great Architect of nature, and lead us to conclude, that mountains, so far from being rude excrescences of nature, as some have asserted, form an essential part in the constitution, not only of our globe, but of all habitable worlds. And this conclusion is confirmed, so far as our observation extends, with regard to the moon, and several of the planetary bodies which belong to our system, whose surfaces are found to be diversified by sublime ramifications of mountain scenery; which circumstance forms one collateral proof, among many others, that they are the abodes of sentient and intellectual beings.

Again, the colouring which is spread over the face of nature indicates the wisdom of the Deity. It is essential to the present mode of our exist ence, and it was evidently intended by the Creator, that we should be enabled easily to recognize the forms and properties of the various objects with which we are surrounded. But were the objects of nature destitute of colour, or were the same unvaried hue spread over the face of creation, we should be destitute of all the entertainments of vision, and be at a loss to distinguish one object from another. We should be unable to distinguish rugged precipices from fruitful hills; naked rocks from human habitations; the trees from the hills that bear them, and the tiled from the untilled lands. "We should hesitate to pronounce whether an adjacent enclosure contained a piece of pasturage, a plot of arable land, or a field of corn; and it would require a little journey, and a minute investigation, to determine such a point. We could not determine whether the first person we met were a solder in his regimentals, or a swain in his Sunday suit; a bride in her ornaments, or a widow in her weeds." Such would have been the aspect of nature, and such the inconveniences to which we should have been subjected, had God allowed us light, without the distinction of colours. We could have distinguished objects only by intricate trains of reasoning, and by circumstances of time, place, and relative position. And, to what delays and perplexities should we have been reduced, had we been obliged every moment to distinguish one thing from another by reasoning! Our whole life must then have been employed rather in study than in action; and, after all, we must have remained in eternal uncertainty as to many things which are now quite obvious to every one as soon as he opens his eyes. We could neither have communicated our thoughts by writing, nor have derived instruction from others through the medium of books: so that we should now have been almost as ignorant of the transactions of past ages, as we are of the events which are passing in the planetary worlds; and, conse quently, we could never have enjoyed a written revelation from heaven, nor any other infallible

guide to direct us in the path to happiness, is the Almighty had not distinguished the rays of light, and painted the objects around us with a diversityof colours,-sc essentially connected are the minutest, and the most magnificent works of Deity. But now, in the present constitution of things, colour characterizes the class to which every individua' belongs, and indicates, upon the first inspection, its respective quality. Every object wears its peculiar livery, and has a distinguishing mark by which it is characterized.

The different hues which are spread over the scenery of the world, are also highly ornamental to the face of nature, and afford a variety of pleasures to the eye and the imagination. It is this circumstance which adds a charm to the fields, the valleys, and the hills, the lofty mountain, the winding river, and the expansive lake; and which gives a splendour and sublimity to the capacious vault of heaven. Colour is, therefore, an essential requisite to every world inhabited by sensitive beings; and we know, that provision has been made for diffusing it throughout all the globes which may exist in the distant regions which our telescopes have penetrated; for the light which radiates from the most distant stars is capable of being separated into the prismatic colours, similar to those which are produced by the solar rays; which furnishes a presumptive proof that thay are intended to accomplish designs in their respective spheres analogous to those which light subserves in our terrestrial habitation-or, in other words, that they are destined to convey to the minds of sentient beings, impressions of light and colour, and consequently, beings susceptible of such impressions must reside within the sphere, or more immediate influence of these far-distant orbs.

The same benevolent design is apparent in the general colour which prevails throughout the scene of sublunary nature. Had the fields been clothed with hues of a deep red, or a brilliant white, the eye would have been dazzled with the splendour of their aspect. Had a dark-blue or a black colour generally prevailed, it would have cast a universal gloom over the face of nature. But an agreeable green holds the medium between these two extremes, equally remote from a dismal gloom and excessive splendour, and bears such a relation to the structure of the eye, that it refreshes, instead of tiring it, and supports, instead of diminishing its force. At the same time, though one general colour prevails over the landscape of the earth, it is diversified by an admirable variety of shades, so that every individual object in the vegetable world can be accurately distinguished from another; thus producing a beautiful and variegated appearance over the whole scenery of nature." Who sees not in all these things that the hand of the Lord hath wrought this ?" If from the earth we turn our attention to the 5

waters, we shall perceive similar traces of the exquisite wisdom and skill of the Author of nature. Water is one of the most essential elementary parts in the constitution of our globe, without which the various tribes of beings which now people it could not exist. It supplies a necessary beverage to man, and to all the animals that people the earth and the air. It forms a solvent for a great variety of solid bodies; it is the element in which an infinitude of organized beings pass their existence; it acts an important part in conveying life and nourishment to all the tribes of the vegetable kingdom, and gives salubrity to the atmospherical regions. Collected in immense masses in the basins of the sea, it serves as a vehicle for ships, and as a medium of communi cation between people of the most distant lanas. Carried along with a progressive motion over the beds of streams and of rivers, it gives a brisk impulse to the air, and prevents the unwholesome stagnation of vapours; it receives the filth of populous cities, and rids them of a thousand nui sances. By its impulsion it becomes the move? of a multitude of machines; and, when rarefied into steam, it is transformed into one of the most powerful and useful agents under the dominion of man. All which beneficial effects entirely depend on the exact degree of density, or specific gravity, which the Creator has given to its constituent parts. Had it been much more rarified than it is, it would have been altogether unfit to answer the purposes now specified; the whole face of the earth would have been a dry and barren waste; vegetable nature could not have been nourished. our floating edifices could not have been supported; the lightest bodies would have sunk, and all regular intercourse with distant nations would have been prevented. On the other hand, had its parts been much denser than they are; for example, had they been of the consistency of a thin jelly, similar disastrous effects would have inevitably followed; no ships could have ploughed the ocean; no refreshing beverage would have been supplied to the animal tribes; the absorbent vessels of trees, herbs, and flowers would have been unable to imbibe, the moisture requisite for their nourishment; and we should thus have been deprived of all the beneficial effects we now derive from the use of that liquid element, and of all the diversified scenery of the vegetable world. But the configuration and consistency of its parts are so nicely adjusted to the constitution of the other elements, and to the wants of the sensitive and vegetable tribes, as exactly to subserve the ends intended in the system of nature.

Water has been ascertained to be a compound body formed by the union of two different kinds of air-oxygen and hydrogen. It has the property of becoming, in certain cases, much lighter than air; though, in its natural liquid state, it is 800 times heavier than that fluid; and has also

the property of afterwards resuming its natural weight. Were it not for this property, evaporation could not be produced; and, consequently, no clouds, rain, nor dew, could be formed, to water and fertilize the different regions of the earth. But, in consequence of this wonderful property, the ocean becomes an inexhaustible cistern to our world. From its expansive surface are exhaled those vapours which supply the rivers, and nourish the vegetable productions of every land. "The air and the sun," says an elegant writer, "constitute the mighty engine which works without intermission to raise the liquid treasure; while the clouds serve as so many aqueducts to convey them along the atmosphere, and distribute them, at seasonable periods, and in regular proportions, through all the regions of the globe."

Notwithstanding the properties now stated, motion was still requisite, to ensure all the advantages we now derive from the liquid element. Had the whole mass of waters been in a stagnant state, a thousand inconveniences and disastrous consequences would have inevitably ensued. But the All-wise Creator has impressed upon its various masses a circulating motion, which preserves its purity, and widely extends its beneficial influence. The rills pour their liquid stores into the rivers; the rivers roll their watery treasures into the ocean; the waters of the ocean, by a libratory motion, roll backwards and forwards every twelve hours, and, by means of currents, and the force of winds, are kept in constant agitation. By the solar heat, a portion of these waters is carried up into the atmosphere, and, in the form of clouds, is conveyed by the winds over various regions; till, at last, it descends in rain and dew, to supply the springs "which run among the hills." So that there is a constant motion and circulation of the watery element, that it may serve as an agent for carry ing forward the various processes of nature, and for ministering to the wants of man and beast. In fine, were the waters in a state of perpetual stagnation, the filth of populous cities would be accumulated to a most unwholesome degree; the air would be filled with putrid exhalations; and the vegetable tribes would languish and die. Were they deprived of the property of being evaporated, (in which state they occupy a space 1400 times greater than in their liquid state,) rain and dew could never be produced, and the earth would be turned into "a dry and parched wilderness;" neither grass nor corn could be sufficiently dried to lay up for use; our clothes, when washed, could never be dried ; and a variety of common operations, which now conduce to our convenience and comfort, could never be carried on. But the infinite wisdom of the Creator, foreseeing all the effects which can possibly arise from these principles of nature, has effectually provided against such disasters,

by arranging all things, in number, weight and measure, to subserve the beneficial ends for which they were ordained. "He causeth the vapours to ascend from the ends of the earth. he sendeth the springs into the valleys, which run among the hills. They give drink to every beast of the field; the wild asses quench their thirst. By them the fowls of heaven are refreshed, which sing among the branches. He watereth the hills from his chambers, and the earth is satisfied with the the fruit of his works."

Let us now attend to the atmosphere, in the constitution of which the wisdom of God is no less conspicuous than in the other departments of nature. The atmosphere is one of the most essential appendages to the globe we inhabit, and exhibits a most striking scene of Divine skill and omnipotence. The term atmosphere is applied to the whole mass of fluids, consisting of air, vapours, electric fluid, and other matters, which surround the earth to a certain height. This mass of fluid matter gravitates to the earth, revolves with it in its diurnal rotation, and is carried along with it in its course round the sun every year. It has been computed to extend about 45 miles above the earth's surface, and it presses on the earth with a force proportioned to its height and density. From experiments made by the barometer, it has been ascertained, that it presses with a weight of about 15 pounds on every square inch of the earth's surface; and, therefore, its pressure on the body of a middle-sized man, is equal to about 32,000 lbs. or 14 tons avoirdupois, a pressure which would be insupportable, and even fatal, were it not equal in every part, and counterbalanced by the spring of the air within us. The pressure of the whole atmosphere upon the earth, is computed to be equivalent to that of a globe of lead 60 miles in diameter, or about 5,000,000,000,000,000 tons; that is, the whole mass of air which surrounds the globe, compresses the earth with a force or power equal to that of five thousand millions of millions of tons. * This amazing pressure is however, essentially necessary for the preservation of the present constitution of our globe, and of the animated beings which dwell on its surface. It prevents the heat of the sun from converting water, and all other fluids on the face of the earth, into vapour; and preserves the vessels of all organized beings in due tone and vigour. Were the atmospherical pressure entirely removed, the elastic fluids contained in the finer vessels of men and other animals, would inevitably burst them, and life would become extinct ;† and most

• See Appendix, No. II.

of the substances on the face of the earth, particularly liquids, would be dissipated into vapour. The atmosphere is now ascertained to be a compound substance, formed of two very different ingredients, termed oxygen and nitrogen gas. Of 100 measures of atmospheric air, 21 are oxygen, and 79 nitrogen. The one, namely, oxygen, is the principle of combustion, and the vehicle of heat, and is absolutely necessary for the support of animal life, and is the most powerful and energetic agent in nature. The other is altogether incapable of supporting either flame or animal life. Were we to breathe oxygen air, without any mixture or alloy, our animal spirits would be raised, and the fluids in our bodies would circulate with greater rapidity; but we should soon infallibly perish by the rapid and unnatural accumulation of heat in the animal frame. If the nitrogen were extracted from the air, and the whole atmosphere contained nothing but oxygen, or vital air, combustion would not proceed in that gradual manner which it now does, but with the most dreadful and irresistible rapidity: not only wood and coals, and other substances now used for fuel, but even stones, iron, and other metallic substances, would blaze with a rapidity which would carry destruction through the whole expanse of nature. If even the proportions of the two airs were materially altered, a variety of pernicious effects would instantly be produced. If the oxygen were less in quantity then it now is, fire would lose its strength, candles would not diffuse a sufficient light, and animals would perform their vital functions with the utmost difficulty and pain. On the other hand, ware the nitrogen diminished, and the oxygen increased, the air taken in by respiration would be more stimulant, and the circulation of the animal fluids would become accelerated; but the tone of the vessels thus stimulated to increased action would be destroyed by too great an excitement, and the body would inevitably waste and decay. Again, were the oxygen completely extracted from the atmosphere, and nothing but nitrogen remained, fire and flame would be extinguished, and instant destruction would be carried throughout all the departments of vegetable and animated nature. For a lighted taper will not burn for a single moment in nitro

Acosta, in his relation of a journey among the mountains of Pert, states, that "he and his companions were surprised with such extreme pangs of straining and vomiting, not without casting up of blood too, and with so violent a distemper, that they would undoubtedly have died had they remained two or three hours longer in that elevated situation." Count Zambeccari, and his companions, who ascended in a balloon, on the 7th of November, 1783, to a great height, found their hands and feet so swelled, that It was necessary for a surgeon to make incisions In the skin. In both the cases now stated, the persons ascended to so great a height that the pressure of the atmosphere was not sufficient to counterbalance the pressure of the fluids of the body. 35

gen gas, and if an animal be plunged into it, it is instantly suffocated.

Again, not only the extraction of any or.e of the component parts of the atmosphere, or the alteration of their respective proportions, but even the slightest increase or diminution of their spe cific gravity, would be attended with the most disastrous effects. The nitrogen is found to be a little lighter than common air, which enables it to rise towards the higher regions of the atmosphere. In breathing, the air which is evolved from the lungs, at every expiration, consists chiefly of nitrogen, which is entirely unfit to be breathed again, and therefore rises above our heads before the next inspiration.-Now, had nitrogen, instead of being a little lighter, been a slight degree heavier than common air, or of the same specific gravity, it would have accumulated on the surface of the earth, and particularly in our apartments, to such a degree as to have produced diseases, pestilence, and death, in rapid succession. But being a little lighter than the surrounding air, it flies upwards, and we never breathe it again, till it enters into new and salutary combinations. Such is the benevolent skil which the Author of Nature has displayed, for promoting the comfort and preservation of every thing that lives.*

Farther, were the air coloured, or were its par ticles much larger than they are, we could never obtain a distinct view of any other object. The exhalations which rise from the earth, being rendered visible, would disfigure the rich landscape of the universe, and render life disagreeable. But the mighty, by rendering the air invisible, has enable us not only to take a delightful and distinct survey of the objects that surround us, but has veiled from our view the gross humours incessantly perspired from animal bodies, the filth exhaled from kitchens, streets, and sewers, and every other object that would excite disgust. Again, were the different portions of the atmosphere completely stationary, and not susceptible of agitation,

The necessity of atmospherical air for the support of life, was strikingly exemplified in the fate of the unhappy men who died in the Black-hole of in the evening, 146 men were forced, at the point of the bayonet, into a dungeon only 18 feet square. They had been but a few minutes confined in this infernal prison, before every one fell into a perspiration so profuse, that no idea can be formed of it. This brought on a raging thirst, the most difficult respiration, and an outrageous delirium. Such was the horror of their situation, that every insult that could be devised against the guard without, and all the opprobrious names that the Viceroy and his officers could be loaded with, were repeated, to provoke the guard to fire upon them, and terminate their sufferings. Before 11 o'clock the same evening, onethird of the men were dead; and before 6 next morning, only 23 came out alive, but most of them in a high putrid fever. All these dreadful effects were occasioned by the want of atmospheric air, and by their breathing a superabundant quantity of the nitrogen emitted from their lungs.

Calcutta. On the 20th of June, 1756, about 8 o'clock