Place one upon the other in each pan of a balance two lead cubes each weighing 573 grains. They are in equilibrium in air and in water. Between one pair put a strip of cork, the so-called absolute weight of which is 6 grains. The pan containing the cork descends in air with a force exactly as the 6 grains. Immerse both pans in water; the pan with the cork rises with a force as the excess of the specific gravity of water over that of the cork, and 28 grains must be added to the other side to restore equilibrium. And thus an addition of matter here produces a decrease of weight in water.
Further, suppose the excess of the specific gravity of air over that of phlogiston is as the excess of that of water over that of cork, and also that the ratio of the gravity of a certain metallic earth to that of phlogiston is as that of lead to that of cork, and that the aggregate is as 573 to 6, then the earth metallized by the phlogiston will suffer a decrease of weight in air of 28 in 573, that is from 1/20 to 1/21, which it will recover on loss of phlogiston. Here therefore is a diminution of weight in air by accession of matter, and vice versa.
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