Cords on rollers: what weight at m lifts 10 pounds at n
How winding a cord more times around a drum changes the pull needed
Written upside down, the note poses a mechanics problem about two weights joined by a cord that passes around a roller (subbio): what load at point m is needed to raise 10 pounds at n. Leonardo proposes to test, step by step, how the winning weight changes as the cord is wound once, twice, three or four times around the roller, and again when the roller is triangular, square or many-sided. Below the text, pen drawings show cylindrical drums and rollers with cords and hanging weights.
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What weight at m raises 10 pounds at n
The problem asks how much weight must be placed at m to pull 10 pounds at n, and how to learn step by step which of two weights will overcome the other. The variable is the connecting cord that runs from one weight to the other, wound now once around the roller, now two, three or four times. The same test is proposed for rollers that are triangular, square, or of more angles.
Rollers and drums with wound cords
Below the text are drawn cylindrical rollers and stacked drums with cords wrapped around them and balls hanging from the cords. The drawings illustrate the winding arrangement described in the note, showing the cord looping the drum before its weight.