Bending a body by a cord: powers of the motors a b c d e
Pulling lines proportioned to t r; two figures distinguished, pole n and the arc of right angles
The recto continues the analysis of inclining a heavy body (X n y z, weight 8) by a cord fastened at a corner and drawn along many lines. Leonardo states that the powers of the motors a, b, c, d, e stand to the resistance r t as their lines stand to t r, with the fixed corner n serving as the pole. He carefully separates the overlapping constructions into two distinct figures and describes the arc, drawn from the centre on line f n, along which the cords meet the levers at right angles. Several diagrams show rectangles set within circles with fans of labelled lines.
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Powers of the motors proportioned to the pulling lines
Whatever proportion each of the lines t v, t X, t o, t n, t m has to the line t r, such is the power of the motors a b c d e, with r t as the resistance and the pole. The powers of the pulling cords are thus read off geometrically from their lengths.
Inclining the body X n y z about pole n
To incline the body X n y z, a cord is fixed at corner X and pulled along the lines a X, b X, c X and the rest, corner n staying fixed as pole. The spiritual levers X n, S n, t n, v n and others, set against the material lever n m, give oppositely the power of the motor to the power of the weight.
The arc of right angles struck from the centre on line f n
The line f n holds the centre of the circle from which the drawn arc springs. At the contact of that arc the right angles are generated where the cord f a meets the lever a n, and likewise for the others; a n, b n, c n, d n are different lengths of the balance arm n m, with 8 libbre at m.