Accidental weight in angled cords, and the potential lever
How bending a cord multiplies weight; levers, appendages and counter-levers
Folio 9v holds that accidental weight is created from natural weight: as the axle r t of the angled cord c t d is halved, the weight o doubles from 2 to 4, so endless halving would give endless multiplication of weight; and it argues that a cord tangent to the ends of a shaft d e cannot suspend it without forming an angle at b. Folio 6r states that every heavy body weighs along the line of its motion and that its heaviest part guides that motion, then works potential levers, for instance a double lever d b where one pound at d n makes the cord a e b feel 12 pounds. Diagrams of suspended weights, angled cords and pulleys fill both leaves, and further untranscribed calculation is present.
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Bending a cord doubles the hanging weight
Accidental weight is created from natural weight: the accidental weight grows in the sides of the angled cord c t d as much as the axle r t of its angle diminishes. When the axle is halved, the weight o rises from 2 to 4 at c, d; and endless subdivision of the axle would give endless multiplication of weight on the hypotenuses.
A cord cannot hold a shaft without an angle
If a cord d b e is fixed tangent to the ends of the shaft d e, it is impossible to tie another cord a b to suspend the shaft without an angle forming. The angle b is made by necessity of the shaft's weight from the cord that was before tangent to it.
A body weighs along the line of its motion
Every heavy body weighs along the line of its motion, whether violent or natural, curvilinear or straight; the support loads itself entirely with the weight joined to it. The heaviest part guides the motion, and the central line of motion passes through the centre of the heaviest part, of the lightest, and of the whole body's gravity.
A double potential lever multiplies to 12 pounds
The potential lever d b is double its counter-lever b c, so one pound on appendage d n equals 6 pounds on the half-real appendage c a, with 6 more pounds of power joined at b. Therefore the cord a e b, for one pound at d n, feels a power of 12 pounds.
The 8 becomes 7, then halved
The 8 that sustained the appendage a p, having passed from p to o, becomes 7 at that appendage, which 7 then divides in half at the appendage o n.
Arms never double without parallel appendages
The greater arms o m and o n are never double one another unless their appendages n a and m p are parallel, which is impossible since they concur to create the angle p. Because o n falls short of being double o m, its appendage n a feels more than half the weight p, and all that surplus is accidental weight.
