Hydrostatics.

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XVI. If a Solid, as G, equal in Weight toan equal Bulk of the Fluid., be immersed there-in, it will take any Situation indifferently inany Part of the Fluid , as at G, H, I, withoutany Pendency to ascend or descend therein:For being totally immersed, it must re-move a Parcel of the Fluid of equal Bulkand Weight; and consequently the Pressure

* upwards

the fame Reason the absolute Weight of a Bulk of thelighter Fluid equal to B will be B b. Let c be theSpecific Gravity of the Solid X ; then the Sum of theWeights of the two Portions of the Fluids must be e-qual to the Weight of the Solid; otherwise it could notbe fustain’d by them : Therefore A a -s- B ^ — X c —

A-j-BXc. Hence A a •— Ar—Be — B b. Conse-quently, A : B c — b : a — c ; and compounding,A : A + B ( — X) :: c — b : a—b.

3. These two Theorems are thus exprefs’d in Words:

1. As the Part of the Solid within the heavier

Fluid is to the Part contain’d within the lighter :So is the Difference between the Specific Gra-vity of the Solid and lighter Fluid, to the Diffe-rence between the Specific Gravity of the Solidand the heavier.

2. The Part of the Solid in the heavier Fluid is tothe whole Solid, as the Difference between theSpecific Gravity of the Solid and lighter Fluid,to the Difference between the Specific Gravityof the two Fluids.

4. Hence, if b~o, we have A : X :: c : a-, that is,the Part immersed is to the whole Solid, as the SpecificGravity of the Solid to the Specific Gravity of the Fluid.And if the two Fluids were Water and Air, Water andOil, or any other, and their Specific Gravities given,with that of the Solid, it will be easy to find the Partsof the Solid contained in either Fluid by the Theoremsabove-mentioned.

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