On Natural Motions Depending on Gravity

IO. AL. BORELLI.

...reason bodies having various sizes, weights, and diverse shapes move with greater or lesser velocity, according to a certain proportion in a fluid medium, no one, as far as I know, has discussed. Therefore, my intention is to explain and supply this part of physico-mechanics Borelli's term for the application of mechanical laws to physical, natural phenomena. that has been lacking until now. However, lest I hold back my readers with a tedious repetition of those things that have been handed down by others, I will assume all those principles taught in the elements of mechanics. These include the nature of the scale, the lever, the pulley, and other matters depending on these instruments or sharing their nature. I will bring forward only those things that have a primary use in this doctrine concerning the natural motions of bodies. I do not intend to cover all motions, but only those that depend on the moving force of gravity.

Concerning the Moments of Solid Weights and of Fluids Floating in the Same Fluids.

original: "De Momentis Gravium consistentium." In this context, "moments" refers to the "momentum" or the tendency of a weight to move around a center, a key concept in 17th-century statics.

CHAPTER II.

Archimedes dealt most subtly and excellently with things floating in water original: "de insidentibus humido," a reference to Archimedes' foundational work On Floating Bodies.. Afterward, Galileo and Stevinus Simon Stevin, a Flemish mathematician and physicist known for his work on hydrostatics and for popularizing decimals. demonstrated these same things by other methods, as truth can be confirmed in innumerable ways. I myself have devised and presented new demonstrations of these same propositions by proceeding along a very different path. I have done this not out of a desire for variety, but because these new proofs are very helpful for the things we must explain later. First, however, some hypotheses must be put forward.