The Ingenious and Curious Pneumatic Motions of Hero

Because if the water must exit from it, it is necessary that the upper part of the pipe first fills itself, into which air cannot enter by any means. Whence, if we pierce it in the upper part, the water will immediately come out, and in place of it the air will succeed. But before said hole is made, the moisture—that is, the water—that is in the pipe strikes against the underlying air, which, not having a place where it can flow, does not let the water come out. But when, by way of the hole, it obtains a place, then it gives way to the water and lets it flow out, filling the place of it. And for this reason, contrary to nature, one attracts wine through the pipe with the mouth; because by drawing the air that is in the pipe, it comes to fill itself much more, and because it is joined to said air, we come to detach it. And this is done until the evacuation is made with the surface of the wine, as was said above, and then the detached wine flows and falls into the evacuated place of the tube, not having another place where it is permitted to flow, and for this reason it is brought upwards against nature. Otherwise, the water will be quiet in the pipe when it is constituted in a spherical surface, the center of which is the same as the center of the earth. For if there is any aqueous surface that has the same

A circular geometric diagram depicting a sphere within a sphere or arcs relative to a central point marked G. A vertical radius line connects G to a point B at the top of the outer circle. Other points on the arcs and lines are labeled A, C, D, and F. The diagram is used to illustrate principles of hydrostatic equilibrium and fluid surfaces.

center that the earth has, it stays quiet; but if it is possible that it does not rest, it is necessary that by moving it pauses. Let it rest, then, so that the center of its spherical surface, being the same as that of the earth, will follow the first surface. Because the water, flowing here and there through one and many places, will have occupied different places. Let it be, therefore, that each of these surfaces, which have their center with the earth, be cut by some plane, and from them are created lines in said surfaces, which are circles of the circumferences that have the same center as that of the earth, that is A. B. C. F. B. D., and let the B. G. be drawn, which because it will be equal to each of these, that is G. F., G. A.—which can be—it is therefore necessary that it rests, and let so much of this be said.

OF THE SPIRITUAL TUBE IN THE MIDDLE OF ANOTHER

Tube in the upper mouth closed. Theor. 11.

There is another sort of pipe or tube, which is called a Middle Spiritual, the reason for which is the same as the past one of the bent pipe. Let the vessel full of water be A. B., in the middle of which is placed the tube C. D., which passing through the foot of said vessel advances below it; but in the upper part, its mouth does not reach the mouth of the vessel A. B., but is surrounded by another tube, the vacuum of which