Levers, the Perfect Balance and a Proof against Pellacane
The line of force at right angles; true weight shown by natural motion; a small weight loading two supports
The page gathers propositions on statics: the line of force always acts on the lever, spiritual or material, at right angles, and in the perfect balance the true weight of a body is shown by the line of its natural motion. A proof against Pellacane's treatment of balances argues that a weight hung farther from the center descends faster, since it describes a straighter (less oblique) line. Diagrams of loaded wheels and levers carry weights marked 10, 10, 10, 10, 10 and 10, 10, 10, 30, and 2 against 200, illustrating the note that a weight of 2 can deliver a hundred to its two supports; the arched figures at the foot show loads carried on paired supports.
On this page
The line of force acts on the lever at right angles
The line of force always operates upon the lever, whether spiritual or material, at equal right angles. The upper-right figure shows the force line meeting the lever arm of a loaded wheel.
The perfect balance and true weight
In the perfect balance, the true weight of each body is shown by the line of its natural motion. The mid-page quadrant figure illustrates the arc of descent used to compare weights.
Proof against Pellacane on balances
Against Pellacane's depiction of balances, Leonardo argues that a weight hung farther from its center descends more quickly than one nearer, because in descending the distant weight describes a straighter line; and a gravity that descends along a less oblique line weighs more and falls faster.
A weight of 2 loading its two supports
It is possible, Leonardo notes, that a weight of 2 delivers a hundred to its two supports. The lower diagrams pair small numbers (2 against 200) with the arched figures at the foot, where loads hang from a series of arches carried on paired supports.