Force of pulley blocks, with arithmetical notes
How to find the force resisting a weight raised on pulley blocks, with red-chalk sums above
With the notebook inverted, this pen note gives a rule for pulley blocks ('taglie'): to find the force resisting a load, divide the load in pounds by the number of wheels in the blocks, and the quotient is the force that balances it with equal power. Above the note, in red chalk, stand columns of figures including 1750, 70, 6000, 350 and 140, the working of an arithmetical calculation.
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Force resisting a weight raised on pulley blocks
If the load is known but not the force, one divides the pounds of the load by the number of wheels in the pulley-blocks (taglie); the result is the force that resists it with equal power. It expresses the mechanical advantage of a compound pulley.
Columns of figures in red chalk
At the head of the page, in red chalk, are several columns of numbers including 1750, 70, 6000, 350 and 140, set out with rules and a repeated total of 1750. They record an arithmetical working.