A Prophecy, and Studies of Levers and a Screw Device
Nature despoiled and the two maladies of music, with the law of the lever and a screw mechanism
Along the upper margin runs a prophecy-like passage: all the animals languish and fill the air with laments, the woods fall in ruin and the mountains are torn open to seize the metals within, while the truly wicked are those who praise men who have harmed their country; a following note holds that music suffers two maladies, one 'mortal' and one 'of decrepitude'. The rest of the sheet develops mechanics — the law of the lever and its counter-lever, a revolving body brought close to the pole, and a screw device driven by a rack and pinion. Lower notes add Latin pen-trials, a small debt owed by one Antonio, and columns of arithmetic.
On this page
Prophecy of despoiled nature, and the maladies of music
The upper margin declares that all the animals languish and fill the air with lamentations, the woods fall in ruin and the mountains are torn open to snatch the metals bred within them, and asks what could be more wicked than praising those who most ardently harmed their country and the human species. A second note holds that music has two maladies, one mortal - bound to the instant after its creation - and one of decrepitude that makes it hateful in repetition.
The law of the lever and counter-lever (b a - c)
Beside a double figure of a joint, lettered b a - c, Leonardo states that where there is no counter-lever the lever gives motion to nothing, and that among levers equal in length the more powerful is the one that has the lesser counter-lever.
Screw device with rack and pinion (a - c - b)
An overall view of a device, lettered a - c - b, shows that a and b always stay one beneath the other because the centre of the screw moves toward c by means of the little rack and the pinion of the screw.
A revolving body near the pole (a - n)
By the larger drawing, lettered a - n, Leonardo directs that the space between a and n be kept minimal and that the centre of the revolving body lie almost at the surface of the pole.
A debt: Antonio to give one pound, ten soldi
A jotting made with the sheet turned records that Antonio is to give (owes) one pound and ten soldi, alongside repeated writings of the name. Columns of arithmetical working appear lower on the page.