Two rods: the lifting power of the longer rod
A proportion problem on lifting, with columns of arithmetic
Leonardo poses a proportion problem: if a rod of half a braccio raises 100, how much will a rod of one braccio raise, being of equal thickness? An 'indeterminate figure' is noted, and columns of arithmetic operations fill the lower part of the sheet. Two graduated rods and a small hanging device are drawn down the right margin.
On this page
If a half-braccio rod raises 100, what will a full braccio raise?
Leonardo asks how the raising power of a rod scales with its length when its thickness is held equal. A rod half a braccio long is said to raise 100, and the question is how much a rod a full braccio long will raise.
Columns of arithmetic operations
The lower page carries several columns of figures worked out in sequence (371, 165, 430, 7930, 1855, 330, 900 and others). They are the calculations attached to the rod problem above.
Graduated rods and a hanging device in the margin
Down the right margin are drawn two graduated (scaled) rods and, below them, a hanging chain carrying a ring. These sketches illustrate the rods and weights of the proportion study.