_Molecula_, the Impetus of whose Gravity surpasses that of the Resistance of the Water, subsides a great deal of it to the _bottom_. Nor does it only fall down it self, but frequently entangling with the _Vegetable Nubeculæ_, forces them down along with it. The Reason why Bodies, when dissolved and reduced to extreme small Parts, are sustain'd in Liquors that are of less specifick Gravity than those Bodies are, hath been pointed at by a late ingenious Member of this Society[7]. He is indeed far from having adjusted all the _Momenta_ of this Affair; however it must be admitted, that, in the _dividing_ or _solution_ of Bodies, their Surfaces do not decrease in the same Proportion that their Bulk does. Now the Gravity of a Body, which is the Cause of its sinking or tendency downwards, is commensurate to its Bulk; but the resistance that the Liquor makes, is proportion'd, not to the Bulk, but to the Extent of the Surface of the Body immersed in it. Whence 'tis plain, a Body may be so far divided, that its Parts may be sustain'd in a Fluid, whose specifick Gravity is less than that of the said Body. Nay, 'tis Matter of Fact, that they frequently are so; and we daily see _Menstrua_ supporting the Parts of _Metals_, and other Bodies, that are of six, ten, nay, almost twenty times the specifick Gravity of those _Menstrua_. And as the Parts of Bodies when divided, are thus supported in a Fluid; so when they occur and unite again, they must sink of course, and fall to the Bottom. Upon the whole, 'tis palpable and beyond reasonable Contest, that _Water_ contains in it a very considerable Quantity of terrestrial Matter. Now the Question is, to which of these, the Water, or the Earthly Matter sustain'd in it, Vegetables owe their Growth and Augment: For deciding of which, I conceive the following Experiments may afford some Light; and I can safely say, they were made with due Care and Exactness. _Anno_ 1691.