Suspended Rod: Working the Weights by Multiplication
A numerical worked example dividing the rod into twelve parts
Two diagrams of a suspended rod appear at the top of the leaf, one larger and one smaller inset, with weights and division marks lettered p, q, S, h, d and q. The note runs through a numerical example: 6 times 8 makes 48, which divided by 12 yields 5 1/3, while 2 times 8 makes 16, which divided by 12 gives 1 1/3, and the same for the other 2. A marginal calculation confirms that the rod is reckoned in 12 parts, each equal to 8/12.
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Distributing the load along a divided rod
The figures show a rod hung by cords with its length marked off in equal divisions and weights lettered along it. The calculation assigns portions of the load to each division, the balance depending on how the weights fall against the marked spaces.
Multiplying and dividing by twelve
Leonardo computes 6 times 8 as 48, divided by 12 to give 5 1/3, then 2 times 8 as 16, divided by 12 to give 1 1/3, repeating for the other 2. The margin records that there are 12 parts in all, into which 8 is divided so that each part is 8/12.