Mechanical studies: spring versus counterweight, siphon and gears
Weight-driven and spring mechanisms with a note comparing their forces
The sheet is crowded with mechanical sketches — toothed wheels, a spring device, weight-driven trains and framed apparatus. A lettered diagram at upper right marks parts ab and ef as fixed and cd as moving, with a profile nm doing its work; a note at left describes mercury drawn through a fine copper tube as a siphon. A long crossed-out passage compares the spring and the counterweight, arguing the spring's power is 'pyramidal' (greatest at the start) while the counterweight combines a constant 'columnar' pull with a 'pyramidal' one.
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Spring compared with counterweight
The crossed-out note asks what difference there is between a spring and a counterweight of equal power, and concludes the spring is always worth more because its power is pyramidal, greatest at the beginning of its motion. The counterweight instead has composite powers: a columnar one that pulls equally throughout, and a pyramidal one that is nil at the start and great at the end.
Lettered apparatus with fixed and moving members
A diagram at upper right is annotated e - c m - na - fb - h, marking a b and e f as stable and c d as mobile. The note adds that the profile n m 'does its office', performing the working motion. It distinguishes the fixed frame from the single moving element of the mechanism.
Mercury drawn through a copper siphon
A note beside an apparatus at left describes 'mercurial silver' (mercury) drawn through a very fine copper wire acting as a siphon. It studies how the heavy liquid can be led through a slender tube. The sentence breaks off unfinished.
Framed weight-driven mechanism
A large device set in a rectangular frame occupies the lower center, with a central column, curved arms and a weighted arc at its base. Toothed wheels and pulleys surround it. It appears to be a weight-driven train of the kind the accompanying notes analyse.