debauch till he has consumed them all, and then goes to war again; the Greenlander, who warms himself with the fragments of wrecks and drift-wood thrown upon the glaciers, and feeds himself with blubber, - seem all to lead lives requiring but little intellectual action; and yet a careful reflection would show that there is not one, even of them, who does not, every moment of his life, call into exercise, though in an humble degree, all the powers of the mind.

In like manner, the philosopher who shuts himself up in his cell, and leads a contemplative existence among books or instruments of science, seems to have no occasion to employ, in their ordinary exercise, many of the capacities of his nature for physical action; although he also cannot act, or even think, but with the aid of his body.

The same Creator who made man a mixed being, composed of body and soul, having designed him for such a world as that in which we live, has so constituted the world, and man who inhabits it, as to afford scope for a great variety of occupations, pursuits, and conditions, arising from the tastes, characters, habits, virtues, and even vices, of men and communities. For the same reason, that, though all men are alike composed of body and soul, no two men probably are exactly the same in respect to either, so provision has been made by the Author of our being for an infinity of pursuits and employments, calling out, in degrees as various, the peculiar powers of both principles.

But I have already endeavored to show that there is no pursuit and no action that does not require the united operation of both; and this of itself is a broad natural foundation for the union into one interest of all, in the same community, who are employed in honest work of any kind, viz., that, however various their occupations, they are all working with the same instruments, - the organs of the body and the

powers of the mind.

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But we may go a step farther, to remark the beautiful process by which Providence has so interlaced and wrought up together the pursuits, interests, and wants of our nature, that the philosopher, whose home seems less on earth than among the stars, requires, for the prosecution of his studies, the aid of numerous artificers in various branches of mechanical industry, and in return furnishes the most important facilities to the humblest branches of manual labor.

Let us take, as a single instance, that of astronomical science. It may be safely said, that the wonderful discoveries of modern astronomy, and the philosophical system depending upon them, could not have existed but for the telescope. The want of the telescope kept astronomical science in its infancy among the ancients. Although Pythagoras, one of the earliest Greek philosophers, by a fortunate exercise of sagacity, conceived the elements of the Copernican system, yet we find no general and practical improvement resulting from it. It was only from the period of the discoveries made by the telescope that the science advanced with sure and rapid progress. Now, the astronomer does not make telescopes.

I presume it would be impossible for a person who is employed in the abstract study of astronomical science to find time enough to comprehend its profound investigations, and to learn and practise the trade of making glass. It is mentioned as a remarkable versatility of talent in one or two eminent observers, that they have superintended the cutting and polishing of the glasses of their own telescopes. But I presume, if there had never been a telescope till some scientific astronomer had learned to mix, melt, and mould glass, such a thing would never have been heard of.

It is not less true that those employed in making the glass could not, in the nature of things, be expected to acquire the scientific knowledge requisite for carrying on those arduous calculations, applied to bring into a system the

discoveries made by the magnifying power of the telescope. I might extend the same remark to the other materials of which a telescope consists. It cannot be used to any pur pose of nice observation without being carefully mounted on a frame of strong metal, which demands the united labors of the mathematical instrument maker and the brass founder.

Here, then, in taking but one single step out of the philosopher's observatory, we find he needs an instrument to be produced by the united labors of the mathematical instrument maker, the brass founder, the glass polisher, and the maker of glass, -four trades. He must also have an astronomical clock, and it would be easy to count up half a dozen trades, which directly or indirectly are connected in making a clock. But let us go back to the object glass of the telescope.

A glass factory requires a building and furnaces. The man who makes the glass does not make the building. But the stone and brick mason, the carpenter and the blacksmith, must furnish the greater part of the labor and skill required to construct the building. When it is built, a large quantity of fuel, wood and wood-coal, or mineral coal of various kinds, or all together, must be provided; and then the materials of which the glass is made, and with which it is colored, some of which are furnished by commerce from different and distant regions, and must be brought in ships across the sea.

THE SAME, CONCLUDED.

WE cannot take up any one trade without immediately finding that it connects itself with numerous others. Take, for instance, the mason who builds the furnace. He does not make his own bricks, nor burn his own lime: in common r 185, 195. y 158, 161.

cases, the bricks come from one place, the lime from another, the sand from another. The brick maker does not cut down his own wood. It is carted or brought in boats to his yard. The man who carts it does not make his own wagon; nor does the person who brings it in boats build his own boat. The man who makes the wagon does not make the tire.

The blacksmith who makes the tire does not smelt the ore; and the forgeman who smelts the ore does not build his own furnace, (and there we get back to the point whence we started,) nor dig his own mine. The man who digs the mine does not make the pickaxe with which he digs it, nor the pump with which he keeps out the water. The man

who makes the pump did not discover the principle of atmospheric pressure, which led to pump making; this was done by a mathematician at Florence, experimenting in his chamber on a glass tube.

And here we come back again to our glass, and to an instance of the close connection of scientific research with practical art. It is plain that this enumeration might be pursued till it was shown that every art and every science runs into every other. No one can doubt this who will go over the subject in his own mind, beginning with any one of the processes of mining and working metals, of ship-building, and navigation, and the other branches of art and industry pursued in civilized communities.

If, then, on the other hand, the astronomer depends for his telescope on the ultimate product of so many arts, in return, his observations are the basis of an astronomical system, and of calculations of the movements of the heavenly bodies, which furnish the mariner with his best guide across the ocean. The prudent ship-master would no more think of sailing for India without his Bowditch's Practical Navigator, than he would without his compass; and this Navigator contains tables drawn from the highest walks of astronomical science. Every first mate of a vessel, who

works a lunar observation to ascertain the ship's longitude, employs tables in which the most wonderful discoveries and calculations of La Place, and Newton, and Bowditch, are interwoven.

I mention this as but one of the cases in which astronomical science promotes the service and convenience of common life; and perhaps, when we consider the degree to which the modern extension of navigation connects itself with industry in all its branches, this may be thought sufficient. I will only add, that the cheap convenience of an almanac, which enters into the comforts of every fireside in the country, could not be enjoyed but for the labors and studies of the profoundest philosophers.

Not that great learning or talent is now required to execute the astronomical calculations of an almanac, although no inconsiderable share of each is needed for this purpose; but because even to perform these calculations requires the aid of tables which have been gradually formed on the basis of the profoundest investigations of the long line of philosophers, who have devoted themselves to this branch of science. For, as we observed on the mechanical side of the illustration, it was not one trade alone which was required to furnish the philosopher with his instrument, but a great variety, so, on the other hand, it is not the philosopher in one department who creates a science out of nothing.

The observing astronomer furnishes materials to the calculating astronomer, and the calculator derives methods from the pure mathematician; and a long succession of each for ages must unite their labors in a great result. Without the geometry of the Greeks, and the algebra of the Arabs, the infinitesimal analyses of Newton and Leibnitz would never have been invented.

Examples and illustrations equally instructive might be found in every other branch of industry. The man who will go into a cotton mill, and contemplate it from the great m 185, 204.

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