Percussion notes, grain from a sieve, and a pulley-raised stair
Motion studies beside a fortress wall and a hoisting mechanism
Written with the page inverted, the sheet gathers short mechanical queries beside quick diagrams. Grain thrown up from a sieve is said to leap in a pyramidal form, and a note asks how percussion differs between a joined and a disjoined body struck by a hammer. Further sketches show a fortress wall six braccia thick and a kind of stairway raised by ropes and pulleys.
On this page
Grain leaps pyramidally from the sieve
Grain tossed upward with a sieve is observed to rise in a pyramidal spread. A small diagram shows the scattered grains fanning out above and below a shaken plane. The note treats the trajectory of the flung particles as a study in motion.
Percussion of joined versus disjoined bodies
A thing moves further in derivative motion the more it is accompanied by its mover. The note then asks what difference there is in the percussion of a body that is joined compared with one that is disjoined, prompted by small objects rebounding from a board struck with a hammer.
Stairway raised by ropes and pulleys
A kind of stair or ladder is shown being lifted by cords running over pulleys. Only the caption names the device; no descriptive text accompanies it. Looping lines in the drawing correspond to the rigging.
Fortress wall, six braccia
A fragment records a fortress wall carrying the dimension six braccia. It sits among the mechanical sketches at the head of the sheet. No further specification is given in the bundle.