texture. The fragrance of flowers also results from the same. refined secretions, whose colours are brought out by so little of that matter, so much of which is necessary for developing the same in grosser substances, as metallic and earthy bodies. Common leaves and grass, being of a less delicate texture, have only the darker colour of green brought forth by the same quantity of light, which brings out the liveliest tints of flowers.

The fanciful colours of clouds and vapour, which intervene between us and the setting sun, are illuminations of those bodies by the opposite sunbeams, developed oftentimes in the very contrary way from what they should be, if consisting of reflected light; since the rays and their reflection are wholly concealed from us by the coloured vapour. Warm blood owes its redness to the heat it contains, since when it is brought into the air and left to cool, it turns to a dark hue.

ON THE PLANETARY MOTIONS.

GRAVITATION is with propriety extended to the planets and satellites, which revolve about the sun. They may all have a tendency to fall down to the sun or their primaries in the same way as a stone hurled into the air has a tendency to fall to the earth. This law, however, is not wholly universal, since fire, the most extensive of all the elements of matter, pervading all the planets as well as the earth, blazing in the stars as well as the sun, and stretching throughout all the immensity of space, is itself imponderable, darting upward as easily as. downward, and diffusing itself with the rapidity of lightning through all bodies. When it is emitted from a candle, it flows off in every direction with equal ease and velocity, and, indeed, it is constantly 'issuing from the sun in directions contrary to gravity.'

But has the sun itself no weight? If his fiery part has none, yet his combustible part may, and it is necessary that a part of the sun's body should consist of passive, cohering, and combustible matter in order not only to support his flames, but also his very form and compact mass, for if fire has not a sufficient attraction or affinity among its own particles, it would be impossible for it to subsist, independent of any other matter, in a fixed body by itself. Allowing the sun, then, to have weight, whither shall he fall when all other bodies are falling to him? Is he supported in his fixed position solely by his gravitation in different directions to the bodies, that move about him? If this were the sole cause of his fixedness, would there not be some

danger among all the diverse revolutions and masses of the planets and numerous wild comets, and withal of the decay or change, which these masses may undergo in time, that the same quantities of matter would not always be found on the different sides of him, or that a greater quantity would not sometimes collect on one side than the other, and so draw him off from his centre? It seems, that no less than Infinite Power were able to preserve this constant equilibrium of the heavenly bodies, if it were gravitation only, which held the sun in his place. Hence, I conceive, that another very important concurring cause of this consists in the electric repulsion which the sun sends off in his rays in all directions, thus procuring him a sort of independence of his satellites for his standing in the midst of them. Electricity consisting of pure fire like the sun's, and he sending off this fire in such continual torrents, what hinders that he should send off immense powers of electric repulsion in these torrents to resist the gravitation of his satellites towards him, and to be a principal cause of his own firm and fixed position in the midst of them, seeing that they are so dependent on him for their life, light, and support?

Knowing that the electric fluid consists of fire, and consequently, that electricity is a property of fire, it is certain that the great fountain and source of fire must possess vast powers of electricity, and like a highly electrified body be able to send off great forces of repulsion in the direction of its rays. Nor are its electric powers in danger of failing, since its emission of fire is perpetual. What then is so agreeable to nature and experience, the order of the heavens and the system of the universe, as to suppose that the motions of the planets are governed by the powers of the solar fire? being all kept at their distances, as they revolve about it, by the force of its electric repulsion? The planets being electrified by the sun's rays, what is more certain or strictly accordant to all electrical phenomena, than that they should be repelled from him?

While at the same time their gravitation towards him offers a resistance to this force, which might otherwise drive them wholly off, and keeps the planet at just such an equable distance from the sun, as where the gravitating and repelling forces equal each other, and hold an equilibrium. We have no need of building up this doctrine on the dark faith of mathematical diagrams, and calling to aid all that is abstruse, I will not say to hide its defects. We have direct experience to confirm it, and numberless experiments. What are better known than the powers of gravitation and electric repulsion? Take away the force of repulsion from the sun, and let the heavens go on according to the system which astronomers have taught, and observe some few of the inconsistences, which arise. All the planets gravitating to the sun and the sun to the planets, what great and constant force is it which keeps them from rushing together? The centrifugal force of the planets. From whence does this force arise? From the original impulse or projectile force which they received from the hands of their Creator on being first launched into space. Is this the only cause of the centrifugal force? Ay. How is it, that this force is not impaired by length of time, as all other forces, which arise from single impulses? No resistance is made to it, that might overcome it, as there is no etherial substance in the heavenly spaces, which might oppose the progress of the planet through it. Granting this, yet does not gravitation offer a constant resistance to the force of original impulse? Nay. What? Gravitation offers no resistance to projectile force? Is it not the weight of a cannon ball, which overcomes the impulse the cannon gives it, and is almost the sole cause which brings it to the ground? When a stone is hurled into the air, is it not the stone's weight, which quickly overcomes the force that sends it? Is it not gravitation, that brings all bodies directly downward, whatever be the force which for a moment opposes this tendency? By what wonderful exception, then,

to all experience is it, that when a planet is hurled into space, it should not fall down to the sun, as a stone does to the earth? Away with mathematical sophistry and vain imaginations averse to all experience. So sure as it is a stone's weight, which overcomes the impulse, which sends it into the air, and brings it down to the earth, so sure is it, that it is a planet's weight, which, after making all allowance for diversity of circumstance, must presently bring it downward to the sun, if there existed no repulsion to oppose it, and with the utmost violence. It is in vain to pump the heavens empty of all etherial substance; the planet would then fall so much the quicker and more heavily, as it is well known, that even the lightest feather in the vacuum of an air-pump will fall like a stone. Nor, if it were possible for a planet to revolve about the sun merely from the cooperating influences of gravitation and projectile force could the planet be said to resist any predominating influence of gravity by any increasing impetus it might acquire, the further it proceeded on a half falling course; for although a body falling a great distance directly downward may acquire increasing force the further it falls, yet wherever a body moves in a circle or ellipse, no such thing is known to take place.

How untrue then is the common theory of the cause of planetary motions; fictitious, and averse to all, ay, and the commonest experience. It supposes, that if a cannon ball were shot off from a high mountain into a firmamental vacuum, it would never fall to the earth, but go on incessantly revolving about it in precisely the same orbit. (Cambridge Physics, Ast. p. 345.) But the largest ball, that was ever yet thrown off from a high mountain with the utmost force, that could be put to it, never travelled but a very short distance, before it came to the earth with violence. And shall a vacuum diminish this obstruction of gravity to simple impulse? On the contrary, is it not known from experiment, that the overcoming influence of