Heronis Alexandrini spiritalium liber

continues from previous page: exists together with the vessel, let it be lowered into water; then, the vessel being uncovered and having its opening facing upward, let the water enter; indeed, the air departs from the vessel; but, overcome by the quantity of water, it is again mixed and entangled, so that it becomes water. In the same way, the air in a cupping-glass being corrupted and attenuated by fire, and having escaped through the rarities of the vessel, the emptied interior place attracts the surrounding matter, whatever it may be. But when the cupping-glass has breathed again, air succeeds into the evacuated place, the matter no longer being attracted. Therefore, those who say universally that there is nothing empty at all can devise many arguments for these things, and perhaps persuade more by speech, although they bring forth no sensible demonstration. But if it is shown in those things which appear and fall under the senses that a vacuum indeed is amassed against nature, but by nature there is a vacuum disseminated in small parts, and that bodies themselves are disseminated through compression to fill empty spaces, those who bring forth plausible reasons about these things will no longer be heard in any way.