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waves which confound the heaven and the sea, are doing the very thing which was done in the bottle. Nothing can be of greater importance to the living creation, than the salubrity of their atmosphere. It ought to reconcile us, therefore, to these agitations of the elements, of which we sometimes deplore the consequences, to know, that they tend powerfully to restore to the air that purity, which so many causes are constantly impairing.

II. In water, what ought not a little to be admired, are those negative qualities which constitute its purity. Had it becn vinous, or oleaginous, or acid; had the sea been filled, or the rivers flowed, with wine or milk; fish, con stituted as they are, must have died; plants, constituted as they are, would have withered; the lives of animals which feed upon plants, must have perished. Its very insipidity, which is one of those negative qualities, renders it the best of all menstrua. Having no taste of its own, it becomes the sincere vehicle of every other. Had there peen a taste in water, be it what it might, it would have infected everything we ate or drank, with an importunate repetition of the same flavor.

Another thing in this element, not less to be admired, is the constant round which it travels; and by which, with out suffering either adulteration or waste, it is continually offering itself to the wants of the habitable globe. From the sea are exhaled those vapors which form the clouds; these clouds descend in showers, which, penetrating into che crevices of the hills, supply springs; which springs flow in little streams into the valleys; and there, uniting, become rivers; which rivers, in return, feed the ocean. So there is an incessant circulation of the same fluid; and not one drop probably more or less now than there was at the creation. A particle of water takes its departure from the surface of the sea, in order to fulfil certain important offices to the earth; and, having executed the service which was assigned to it, returns to the bosom which it left.

Some have thought, that we have too much water upon the globe, the sea occupying above three quarters of its whole surface. “But the expanse of ocean, immense as it is, may be no more than sufficient to fertilize the earth. Or, independently of this reason, I know not why the sea may not have as good a right to its place as the land. It may proportionably support as many inhabitants; minister to as large an aggregate of enjoyment. The land only affords a habitable surface; the se: is habitable to a great depth.

III. Of fire, we have said that it dissolves. The only idea probably which this term raised in the reader's mind, was that of fire melting metals, resins, and some other substances, fluxing ores, running glass, and assisting us in ma..y of our operations, chemical or culinary. Now these are only uses of an occasional kind, and give us a very imperfect notion of what fire does for us. The grand inportance of this dissolving power, the great office indeed of fire in the economy of nature, is keeping things in a state of solution, that is to say, in a state of fluidity. Were it not for the presence of heat, or of a certain degree of it, al. fluids would be frozen. The ocean itself would be a quarry of ice; universal nature stiff and dead.

We see, therefore, that the elements bear not only a strict relation to the constitution of organized bodies, but a relation to each other. Water could not perform its office to the earth without air; nor exist, as water, without fire.

IV. Of light, (whether we regard it as of the same substance with fire, or as a different substance,) it is altogether superfluous to expatiate upon the use. No man disputes it. The observations, therefore, which I shall offer, respect that little which we seem to know of its constitution.

Light travels from the sun at the rate of twelve million of miles in a minute. Urged by such a velocity, with what force must its particles drive against, (I will not say the eye, the tenderest of animal substances, but) every substance, animate or inanimate, which stands in its way! It might seem to be a force sufficient to shatter to atoms the hardest bodies.

How then is this effect, the consequence of such pron digious velocity, guarded against? By, a proportionable minuteness of the particles of which light is composed. It is impossible for the human mind to imagine to itself anything so small as a particle of light. But this extreme er ility, though difficult to conceive, it is easy to prove. A drop of tallow, expended in the wick of a farthing candle, shall send forth rays sufficient to fill a hemisphere of a mile diameter; and to fill it so full of these rays, that an aperture not larger than the pupil of an eye, wherever it be placed within the hemisphere, shall be sure to receive some of them. What floods of light are continually poured from the sun, we cannot estimate; but the immensity of the sphere which is filled with its particles, even if it reached no farther than the orbit of the earth, we can in some sort compute; and we have reason to believe, that throughout th's whole region, the particles of light lie, in latitude at

least, near to one another. The spissitude of the sun's rays at the earth is such, that the number which falls upon a burning glass of an inch diameter, is sufficient, when concentrated, to set wood on fire.

The tenuity and the velocity of particles of light, as ascertained by separate observations, may be said to be proportioned to each other; both surpassing our utmost stretch of comprehension; but proportioned. And it is this proportion alone which converts a tremendous element into a welcome visiter.

It has been observed to me by a learned friend, as having often struck his mind, that if light had been made by a common artist, it would have been of one uniform color; whereas, by its present composition, we have that variety of colors which is of such infinite use to us for the dis tinguishing of objects; which adds so much to the beauty of the earth, and augments the stock of our innocent pleasures.

With which may be joined another reflection, viz. that, considering light as compounded of rays of seven different colors, (of which there can be no doubt, because it can be resolved into these rays by simply passing it through a prism,) the constituent parts must be well mixed and blended together, to produce a fluid so clear and colorless as a beam of light is, when received from the sun.

CHAPTER XXII.

ASTRONOMY.*

My opinion of astronomy has always been, that it is not ihe best medium through which to prove the agency of an intelligent Creator; but that, this being proved, it shows, beyond all other sciences, the magnificence of his opera tions. The mind, which is once convinced, it raises to sublimer views of the Deity than any other subject affords; but it is not so well adapted as some other subjects are to the

purpose of argument. We are destitute of the means of examining the constitution of the heavenly bodies. The very simplicity of their appearance is against them.

* For the articles in this chapter marked with an asterisk, I am indebte to some obliging communications received (through the hands of the Lord Bishop of Elphin) from the Rev. J. Brinkle D D. Andrew's Professor of Astronomy in the University of Dublin.

nee nothing but bright points, luminous circles, or the phases of spheres reflecting the light which falls

upon

them. Now we deduce design from relation, aptitude, and correspondence of parts. Some degree therefore of complexity is necessary to render a subject fit for this species of argument. But the heavenly bodies do not, except perhaps in the instance of Saturn's ring, present themselves to our observation as compounded of parts at all. This, which may be a perfection in them, is a disadvantage to us, as inquirers after their nature. They do not come within our mechanics.

And what we say of their forms, is true of their motions. Their motions are carried on without any sensible intermediate apparatus; whereby we are cut off from one principal ground of argumentation-analogy. We have nothing wherewith to compare them; no invention, no discovery, no operation or resource of art, which, in this respect, resembles them. Even those things which are made to imitate and represent them, such as orreries, planetaria, celestial globes, &c. bear no affinity to them, in the cause and principle by which their motions are actuated. I can assign for this difference a reason of utility, viz. a reason why though the action of terrestrial bodies upon each other be, in almost all cases, through the intervention of solid or Auid substances, yet central attraction does not operate in this manner.

It was necessary that the intervals between the planetary orbs should be devoid of any inert matter either fluid or solid, because such an intervening substance would, by its resistance, destroy those very motions which attraction is employed to preserve. This may be a final cause of the difference; but still the difference destroys the analogy.*

Our ignorance, moreover, of the sensitive natures by which other planets are inhabited, necessarily keeps from us the knowledge of numberless utilities, relations, and subserviencies, which we perceive upon our own globe.

After all; the real subject of admiration is, that we understand so much of astronomy as we do. That an animal confined to the surface of one of the planets; bearing a

* The moon has no perceptible atmosphere: and as no effects have been observed like those which would be prodaced by vapors or exhalations from its surface, it is possible that there are no Auids upon it. There is no reason, however, from these circumstances, for denying the existence of sensitive beings upon it, although they must be very differently constituted from ourselves to whor air and water are essentially necessary.--Paxton.

less proportion to it than the smallest microscopic insect * does to the plant it lives upon; that this little, busy, inquisitive creature, by the use of senses which were given to it for its domestic necessities, and by means of the assistance of those senses which it has had the art to procure, should have been enabled to observe the whole system of worlds to which its own belongs; the changes of place of the immense globes which compose it; and with such accuracy, as to mark out, beforehand, the situation in the htavens in which they will be found at any future point of time, and that these bodies, after sailing through regions of void and trackless space, should arrive at the place where they were expected, not within a minute, but within a few seconds of a minute, of the time prefixed and predicted: all this is wonderful, whether we refer our admiration to the constancy of the heavenly motions themselves, or to the perspicacity and precision with which they have been noticed by mankind. Nor is this the whole, nor indeed the chief part of what astronomy teaches. By bringing reason to bear upon observation, (the acutest reasoning upon the exactest observation) the astronomer has been able, out of the confusion (for such it is) under which the motions of the heavenly bodies present themselves to the

eye

of a mere gazer upon the skies, to elicit their order and their real paths.

Our knowledge, therefore, of astronomy is admirable, though imperfect; and, amidst the confessed desiderata and desideranda which impede our investigation of the wisdom of the Deity, in these the grandest of his works, there are to be found, in the phenomena, ascertained circumstances and laws, sufficient to indicate an intellectual agency in three of its principal operations, viz. in choosing, in determining, in regulating ;-in-ehousing, out of a boundless variety of suppositions which were equally possible, that which is beneficial; in determining, what, teft te itsell, had a thousand chances against conveniency, for one in its favor; in regulating subjects, as to quantity and degree, which, by their nature, were unlimited with respect to

Hooke describes a minute animalcule, which he discovered with a microscope, upon a vine. From his data an estimate may be made of its bulk; but it is not so easy to fix upon any determinate quantity for the size of the plant. However, to put the case strongly, let the bulk of it be taken as equal to that of a cylinder one inch in diameter and a mile in lengin. Such a cylinder would contain above 345 cubic feet, and yet it would be many million times less when compared with the animalcule, than the earth is when compared with the bulk of a man. - Paxton.

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