Corpus Hermeticum with Pneumatica and Ocellus Lucanus

This occurs because a contraction systolē original: "συστολή" (systolē). In this context, Hero is describing what we now call compression. takes place among the particles sōmata original: "σώματα" (sōmata), literally "bodies." Hero uses this term to describe the physical units of air. existing within the sphere, as the voids kena original: "κενά" (kena). These are the microscopic empty spaces interspersed between the particles of air. interspersed between them yield?, or the contraction happens because of the force of the air being squeezed in. If someone, therefore, blows into the vessel and then immediately [covers] the mouth of the small tube? opening?, closing? it with some? finger so it appears? that the air in the sphere is wedged into the entire space. But if one then draws a breath [sucking air out], the air will rush back out again, though the air that was added? is not visible, because there is no void kenon original: "κενὸν" (kenon). Here he refers to a "continuous" or large-scale vacuum. just as [was stated before].

But if, between the pre-existing air, a certain expansion diastolē original: "διαστολή" (diastolē). This refers to the widening or thinning of the air as particles move further apart. occurs through the suction, then again, if someone wishes to draw out the existing air in the sphere—especially through the siphon—a great quantity will follow, without anything else entering? into the sphere in its place at all, just as was said regarding the same matter previously. Thus, by such a manual act, it is demonstrated that a great accumulation of void kenou is created within the sphere. This is distributed? by the neglect? of the remaining particles of air and the space? regarding this, so that they move to fill the place of the particles that were emptied out. For the growth [of the void] occurs even if no [new particles are added] to them.