Statics of cords and pulleys, with a pile-driver
An automatic pile-driver and anti-friction gear; the less-oblique line, the lever a b, and unequal pulleys
The verso pursues the statics of weights, cords and pulleys among a scatter of mechanical inventions. At the head Leonardo sketches an automatic pile-driver, its ram guided by the 'monk', and an anti-friction device sized in braccia. A large diagram of cords and weights argues that a load rising by a less oblique line moves with more labour, and that a weight counts for more the farther its central line lies from its support — worked through with the lever a b, the counter-lever a d, and weights in pounds. Further notes compare three pairs of wheels differing in size, weight or thickness of pole, concluding that unequal pulleys or poles make equal weights fail to appear equal.
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Automatic pile-driver with the 'monk' guide
The right face shows an automatic device for a pile-driver, its falling ram running against a guide-post labelled the 'monk' (monaco).
A weight rising by a less oblique line moves with more labour
In a diagram of cords and weights, the load that rises by a less oblique line is of more laborious motion. If weight e hangs from cord a e, the cord e h that moves it at the right angle a e h costs no labour, since the weight rests wholly on a e; but placed in the rectangle a c g, the cord g c bears the whole weight. A second proposition proves, by the lever a b subdouble to the counter-lever a d, that weight d feels only 2 of its 4 pounds.
Three pairs of wheels conditioned three ways
Three pairs of wheels are set out: the first unequal in size but equal in weight and poles; the second equal in size and poles but varied in weight; the third equal in size and weight but varied in the thickness of their poles.
Equal weights over unequal pulleys do not appear equal
Wheels of unequal weight will not make the weights appear equal: equal weights on the balance's hangers, discharged over unequal pulleys, will not show themselves equal even though the poles be equal. The same holds when the pulley poles are unequal.
Anti-friction device
Beside the pile-driver an anti-friction device is drawn, its members each measured at one braccio.