Pulleys for lifting weights and a geared train
Why a pulley wrapped by less rope moves more easily; gear-tooth counts and forces
The page analyses a pulley (rotella) for raising weights, arguing it moves more easily when a smaller quantity of rope wraps it, and gives two reasons rooted in the non-perpendicular pull of the cords, shown at c (text 2). A table below records gear-tooth counts and arm lengths for a train lettered a, b, c, d (text 4), followed by a column of bare numbers (text 5). The upper drawings show a large screw-press or geared frame set on a trestle table and, at the right, circular diagrams that test cord angles on pulley wheels lettered c, d. A line of mirror-script text across the very top of the sheet is not included in the transcription.
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Why a pulley wrapped by less rope moves more easily
A pulley for drawing up weights moves more easily when touched by less rope, for two reasons. The first: the weight cannot rest wholly on it because the cords from pulley to weight are not on a perpendicular line, as shown at c. The second reason is broken off in the transcription.
Gear-tooth counts and arm lengths for wheels a, b, c, d
A table pairs each wheel with a tooth count and a braccio measure: a has 8 teeth, b 64, d 8, c 16, with arm values of 1/8, 1/16, 1/2 and 1/16 respectively. It closes with the premise that the wheel feels one pound of effort.
Screw-press or geared frame on a trestle table
A large mechanism stands on a four-legged trestle table: a horizontal threaded shaft wound with cord runs through an upright columned frame, with a turned knob or capstan head at the right end. Below it a smaller wheel-and-axle device is sketched.