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"todo. On the Gravity of Bodies. Essa
BODIES'are' endowed with force, which acts at all times, in all places, and in all senses." If a body enTleavours to move towards one point more" forcibly than to another, we say that it gravitates towards that point. For experience teaches us, that bodies are inclined to descend; or, that if they are far from the surface of the earth without support, they fall on it in a perpendicular line. It is by no means in the body itself that we must seek the cause of its weight; for a body which falls, remains in the state it was pot, till some exterior cause changes it. It is equally impossible that the air should occasion 'this gravity, since being itself heavy, it ought rather to lessen the swiftness of the fall of bodies; we must therefore seek the cause elsewhere. Perhaps the opinion nearest truth, is that which supposes the earth to have the virtue of attracting bodies placed at a certain distance, as the magnet attracts iron: or else, possibly, it may be imputed to a foreign substance distributed throughout all bodies. But though we cannot positively ascertain the cause of weight, nothing is more evident than the advantages which accrue from it. Without it we should not be able to move as we do. When we raise the right foot, we make the left to be the centre of gravity. If we then bend our body forward we are near falling; but by putting out the right foot, we prevent the fall, and make a step. Thus out walk is, in some respects, a continual course of falls, during which the centre of gravity is preserved between our feet. This is the reason we bend forward in going up a hill, and backward in coming down it. We also lean forward when we carry a load on our shoulders, and backward when we carry it before us. All this is according to the laws of gravity, which
govern the motions of animals when they walk, swim, or fly. These same laws govern the motions of the immense bodies which roll in the firmament: the sun attracts the planets; and each planet in its turn attracts its satellites; or, what is just the same, the planets gravitate towards the sun, and the satellites towards the planets: for a body made to turn round, always flies in a direct line from its centre, if it meets with no obstacle in its way. It is with the greatest swiftness that the planets run their course; and the moon is not fastened by a chain to our earth. It seems then, as if a motion so rapid as that of the moon, must throw it very far from us in the immeasurable space, if there were not a force which continually pushes it towards our globe, and which counteracts the force that removes it from hence. That first force is the gravitation of the moon towards the earth. If our earth was either lighter or heavier than it is, what would be the consequence? . It would either draw too near or too far from the sun. In the first case, the heat would be insupportable; and in the latter, the cold would be equally so: every thing in our globe would be consumed or frozen. What would then become of the seasons, and many things so indispensable for man, and so necessary for his happiness?... !
Here again, then, o Supreme Wisdom! I find a monument of thy wonders. By the laws of gravity thou givest motion to the celestial bodies, and to all animals. But it is in this that the greatness of thy power and wisdom consists, that the greatest effects are produced by means that appear to us the most insignificant...is is
The Number of Effects in Nature..
The whole constitution of the world may convince us that it is not chance, but a divine power, and a wisdom beyond all conception, which first erected this wonderful fabric, and impressed motion upon its different parts, and regulated the great chain of events depending on and succeeding each other. What variety of effects does the heat of the sun visibly produce! It not only contributes to preserve the life of multitudes of animals, but also to the vegetation of plants, the ripening of corn and fruit, the fluidity of water, the exhalation of vapours, and formation of clouds, without which neither rain nor dew would fall upon the earth. The air, likewise, is so constituted as to fulfil several purposes at once. By means of this element the animal bodies are preserved, and all the vital motions acquire force. It is the air which kindles fire, and nourishes the flame; and by its motion and undulation, conveys every sort of sound to the ear. It gives a spring to the winged animals, and enables them to fly from place to place. It opens to man an easy passage through the seas; the vast expanse of which he could not otherwise cross Cover. It is the air which supports the clouds in the atmosphere, till, becoming too heavy, they fall again in rain. It is the air which prolongs the day by the twilights; and without it, the gift of speech, and the sense of hearing, would be useless to us. All these blessings, and many more, depend on the formation of the air in which we live and breathe. This wonderful element, which surrounds our globe, which is too subtile to be visible to us, and yet so strong that no element can resist its force, is it not a striking proof of the wisdom of our Creator?
The force of gravitation alone, which exists in every thing, holds the earth firm, preserves the mountains, and renders water fluid. It confines the ocean in its depths, and the earth within the circle prescribed. It maintains each being in its place throughout all nature; and preserves between the celestial bodies the proper distance from each other. Who can describe the many properties of water! In general, it serves to dilute, to soften, to mix a great many bodies which we could not otherwise make use of. It is the most wholesome drink, and the best nourishment for plants: it works mills and several other machines. It procures us fish, and brings on its surface the treasures of other regions. How various and innumerable the effects produced by fire! Solid bodies are either melted and made fluid, or become again solid bodies of a different sort, by the help of fire! It makes fluids boil, or reduces them to a vapour; and gives heat to all other bodies, and contributes to give sensation of sight to living creatures.
It is not only in the natural world that we see the greatest variety of effects produced by the same cause: in the moral world also, one single disposition of the mind produces no less variety of effects. Let us, for example, consider the natural disposition we have to love one another. From hence is derived the care of parents for their children; social ties; the connexion of friendship; goodness in those who govern, and fidelity in those who obey. Thus, one single propensity keeps each individual in the circle prescribed, and, forming the bond of human society, is the principle of all virtuous actions, of all laudable pursuits, and of all innocent enjoyment.
Variety in the Stature of Man.
The entire height of the human body varies considerably, and the more or the less is of little consequence. The usual height is from five to six feet. Some people, who live in the northern countries along the frozen seas, are less than five feet. The least people of those known to us inhabit the top of the mountains in the island of Madagascar: they are scarcely four feet high. Many of these dwarfish people came originally from nations of a common stature; and the cause of their degeneracy must certainly be imputed to the climate they inhabit. The extreme cold most of the year there, makes both animals and vegetables small; why should it not have the same effect on man? On the other hand, there are whole nations of a gigantic size: the most famous of them are the Patagonians, who live near the Straits of Magellan. It is asserted that they are from eight to ten feet high, Neither ought it to appear to us impossible, that there should be people taller than the Europeans. Besides the traces that remain of it in history, and in the monuments of antiquity, there have been seen, even in our climates, men above six feet and a half high; who were, notwithstanding, well proportioned, healthy, and capable of all the exercise and labour which require strength and activity.,
Adorable Creator! every thing bears thy stamp: the dwarf as well as the giant; the blade of grass as well as the oak; the worm as well as the elephant.