Thus, the motion of the orbits of the planets from east to west, having its cause in a higher heaven, is called by all violent, without, however, its… - Jean Rey

I answer, and proudly maintain, "That this increase of weight comes from the air, thickened and made heavy, and in some measure rendered adhesive in the vessel by the violent and long—continued heat of the furnace—which air mixes with the calx (its union being assisted by the continual stirring), and attaches itself to its smallest particles—no otherwise than as water, when sand is thrown into it, makes it heavier by moistening it, and adhering to its smallest grains."

[W]e must not only inquire whence these seven ounces are derived, but, moreover, whence that which has replaced the loss of weight, necessarily arising from the enlargement of volume of the tin, by its conversion into calx, and from the vapours and exhalations that have escaped.

Now casting a look on all that moves, I see nothing that ascends by its own proper motion. Water, indeed, rises in a glass, if we throw earth into it; but all will allow, that it is not from any levity that is in the water, but rather, that the earth, by falling to the bottom, makes the water ascend. Now, if water does not acknowledge levity as the cause of this motion upwards, why should air confess it, which ascends in like manner when pressed on by water? Why fire, which does the same? It will be said, I doubt not, that if the upward motion of the elements be not natural to them, it must be violent; whence this absurdity follows, that each obtains its place in the universe by force. To this I answer, that the elements not having the cause of these motions in themselves, they may, so far, be called violent; but that this violence is gentle, and nowise ruinous.