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upon the majestic brow. We may give the countenance that peculiar cast which calls up the lofty, the tender recollection. And we may imagine the departed sage, still existent, and before us, in undecaying strength and beauty. But just lay our hand on this faultless resemblance; the clay of the grave is not colder; it is death with its icy chill!
But commit this departed saint to the gifted spirit of the poet. The veil of the grave is rent; the silent sleeper called up from the couch of corruption, and in the garments of immortality. His actions are grouped around him, in the brightness of their first appearance; his feelings recalled in the freshness of their innocency; and his secret motives are revealed in their innocency with which they were conceived ; and his generous purposes, which perished in the bud, revived, and expanded into fragrant life. You see the whole man, not in cold marble, not in awful abstraction from his fellow beings; but within the warm precincts of friendship, love, and veneration, invested with the sympathies and attributes of real existence.
THE CABINET OF NATURE.
The atmosphere is one of the most essential appen dages 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 surrounds the earth to a certain height. This mass of fuid 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 vigor. 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 of the substances on the face of the earth, particularly liquids, would be dissipated into vapor.
The atmosphere is now ascertained to be a com
* The pressure of the atmosphere is most strikingly illustrated by means of the air.pump. But as few persons, comparatively, possess this instrument, the following experiment, which any person may perform at pleasure, is suffici. ently convincing on this point. Take a common wine glass, and fill it with water; apply a piece of paper over the mouth of the glass; press the paper to the rim of the glass with the palm of the hand; turn the glass upside down ; withdraw the hand from the paper, and the water will be supported by the pressure of the atmosphere. That it is the atmospherical pressure, and not the paper, which supports the water, is evident ; for the paper, instead of being pressed down by the weight of the water, is pressed upward by the pressure of the atmosphere, and appears concave or hollow in the middle. If the flame of a candle be applied to the paper, it may be held for an indefinite length of time, close to the paper, without setting fire to it. The same fact is proved by the following experiment :--Take a glass tube, of any length, and of a narrow bore; put one end of it in a basin of water; apply the mouth to the other end, and draw out the air by suction; the water will immediately rise towards the top of the tube ; and if the finger or thumb be applied to the top of the tube, to prevent the admission of air, and the tube removed from the bason of water, the water in the tube will be supported by the pressure of the atmosphere on the lower end. Again--Take a wine glass, and burn a small bit of paper in it; and, while the paper is burning, press the palm of the hand upon the mouth of the glass, and it will adhere to the hand with considerable force. In this case the pressure of the atmosphere will be sensibly felt; for it will sometics require a consider able force to detach the glass from the hand.
pound substance, formed of two very different ingredients, termed oxygen, and nitrogen gas. Of 100 mea. sures 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 metalic 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 than 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, were 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 nitrogen gas, and if an animal be plunged into it it is instantly suffocated.
Again, not only the extraction of any one of the com ponent parts of the atmosphere, or the alteration of their respective proportions, but even the slightest increase or diminution of their specific 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 evolve ed 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 fies upwards, and we never breathe it again, till it enter into new and salutary combinations. Such is the benevolent skill which the Author of Nature, has displayed, for promoting the comfort and preservation “ of every thing that lives."*
Farther, were the air colored, or were its particles 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 disfi. gure the rich landscape of the universe, and render life disagreeable. But the Almighty, by rendering the air invisible, has enabled us not only to take a delightful
* 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 Cal. cutta. On the 20th of June, 1756, about eight o'clock 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 eleven o'clock the same evening, one third of the men were dead; and before six next morning. only 23.came out alive, but most of them in a high putrid fever. All these dread. ful effects were occasioned by the want of atmospheric air, and by their breath ing a superabundant quantity of the nitrogen emitted from their lungs.
and distinct survey of the objects that surround us, but has veiled from our view the gross humors 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, all nature would soon be thrown into confusion. The vapors which are exhaled from the sea by the heat of the sun would be suspended, and remain for ever fixed over those places from whence they arose. For want of this agitation of the air, which now scatters and disperses the clouds over every region, the sun would constantly scorch some districts, and be for ever hid from others; the balance of nature would be destroyed; navigation would be useless, and we could no longer enjoy the productions of different climates. In fine, were the atmosphere capable of being frozen, or converted into a solid mass, as all other fluids are, (and we know no reason why it should not be subject to congelation, but the will of the Creator,) the lives of every animal in the air, the waters, and the earth, would, in a few moments, be completely extinguished. But the admirable adjustment of every circumstance, in relation to this useful element, produces all the beneficial effects which we now experience, and strikingly demonstrates, that the intelligent Contriver of all things is a wonderful in counsel, and excellent in working.”
From the instances now stated, we may plainly perceive, that if the Almighty had not a particular regard to the happiness of his intelligent offspring, and to the comfort of every animated existence; or, if he wished to inflict summary punishment on a wicked world, he could easily effect, by a very slight change in the constitution of the atmosphere, the entire destruction of the human race, and the entire conflagration of the great globe they inhabit,--throughout all its elementary regions. He has only to extract one of its constituent parts, and the grand catastrophe is at once accomplished. With what a striking propriety and emphasis, then, do the inspired writers declare, that, “ in Him