obstructions which oppose themselves to its descent, it has a tendency to fall or to approach the centre of the earth, by a motion uniformly accelerated; they have rather chosen to suppose a visionary exterior cause, of which they themselves had but an imperfect idea, than admit that these bodies held their motion from their own peculiar nature.
These philosophers, also, notwithstanding they saw above them an infinite number of globes that moved with great rapidity round a common centre, still adhered to their favourite opinions; and never ceased to suppose some whimsical causes for these movements, until the immortal NEWTON clearly demonstrated that it was the effect of the gravitation of these celestial bodies towards each other. Experimental philosophers, however, and amongst them the great Newton himself, have held the cause of gravitation as inexplicable. Notwithstanding the great weight of this authority, it appears manifest that it may be deduced from the motion of matter, by which bodies are diversely determined. Gravitation is nothing more than a mode of moving—a tendency towards a centre: to speak strictly, all motion is relative gravitation; since that which falls relatively to us, rises, with relation to other bodies. From this it follows, that every motion in our microcosm is the effect of gravitation; seeing that there is not in the universe either top or bottom, nor any absolute centre. It should appear, that the weight of bodies depends on their configuration, as well external as internal, which gives them that form of action which is called gravitation. Thus, for instance, a piece of lead, spherically formed, falls quickly and direct: reduce this ball into very thin plates, it will be sustained in
