On Natural Motions Caused by Gravity

...in a machine which seems to have such a great appearance of probability that anyone would swear such a device could easily continue its motion. My excellent friend Clemente Settimi, a student of Galileo Galileo Galilei, the famous Italian astronomer and physicist who was a mentor to many of Borelli's associates., once shared this speculation and mechanical structure with me. Indeed, while he was observing the rotating drums or wheels by which small boats are pulled from one canal to another in Pisa A city in Tuscany, Italy, known for its engineering works and university. and in Belgium by the strength of a single man, who revolves it by treading on its inner, sloping circumference—much like those dogs that rotate spits in kitchens with the same kind of drum—he thought that a drum could be constructed in the same way in which

A circular diagram of a mechanical device, likely a perpetual motion concept. The circle is divided by a vertical line FCG, where C is the center, F is at the top, and G is at the bottom. A horizontal radius extends to point A on the left. The left half of the circle contains labels D and E. Point B is on the right circumference. A crank or handle labeled H is attached at the top of the axis. The left semicircle (FCGA) is shaded with horizontal lines, representing a heavier fluid like water or mercury, while the right side remains mostly unshaded, representing a lighter substance like oil or air.

its left half could perpetually be occupied by a fluid body heavier than the right half, as seen in the accompanying diagram. Let there be a bronze drum AFBG, enclosed by a curved cylindrical bronze surface and by two flat, circular plates, parallel to each other, very well smoothed, and joined and glued to the cylinder. However, inside the cavity of the drum, a flat plate FCG is placed to serve as a diaphragm A dividing wall or partition used here to separate the two different fluids.. One half of the cylinder FCGA is filled with water or mercury Original: "hydrargiro". A heavy liquid metal often used in 17th-century physics experiments., while the other half BFCG is filled with oil or air. The plate FCG is attached and welded to the axis HC. This axis can be held fixed and rotated within the drum and around the fixed center C by a handle H, under the condition that it fits exactly...