Corpus Hermeticum with Pneumatica and Ocellus Lucanus

[It] is equal in weight to itself. And this is not just an empty claim, for those divers kolumbōntes original: "κολυμβῶντες" (kolumbōntes). Hero refers to sponge divers or salvage divers common in the ancient Mediterranean. who go deep down are not crushed by the weight of the water above them. It must be demonstrated in the following way.

Let us imagine that within a vessel, starting from the surface of the object being pressed upon (that is, the surface where the water rests against it), there is a certain body of equal weight isobares original: "ἰσοβαρὲς" (isobares). This describes an object with the same density as the fluid it is in, so it neither sinks nor floats. within the liquid; for the liquids above possess this very quality. Suppose this body is placed into the liquid so that its lower surface fits perfectly against the object being pressed, as if it were the liquid itself, and that it rests there together with the rest of the liquid lying above it.

It is clear, then, that this body neither protrudes significantly above the rest of the liquid, nor will it sink beneath the surface of the liquid above it. For it was demonstrated by Archimedes original: "Ἀρχιμήδει" (Archimēdei). The famous mathematician from Syracuse (c. 287–212 BCE) whose work laid the foundations for hydrostatics. in his work On Floating Bodies original: "ὀχουμένοις" (ochoumenois). Referring to Archimedes’ treatise De iis quae in humido vehuntur, where he defines the laws of buoyancy. that bodies equal in weight to a liquid, when released into that liquid, will neither protrude above it nor sink to the bottom. Thus, it does not exert pressure on the things beneath it.

Even if the force? of the pressing things were removed, the body would remain in the same place. How then can a body exert pressure if it has no downward momentum rhopēn original: "ῥοπὴν" (rhopēn). This refers to the "inclination" or weight that causes a scale to tip or an object to fall.? On the contrary, such a liquid, acting as the same body, will not press upon the things lying beneath it due to both its remaining at rest and its motion?.