Weights on a Wheel and Axle: a Force Analysis
How a load of 800 is felt as 700, 100 or 25 at the wheel-rims, handle and poles
The opening is filled with diagrams of wheels and axles labelled with weights and numbers, worked out through a chain of numbered propositions. Leonardo analyses how a weight of 800 at e o is felt as 700 at the circumference of wheel s, 100 at the circumference of wheel o, and only 25 at the handle g, while at the poles s f it presses more than its true natural weight. Citing his 3rd, 5th, 7th and 9th propositions, he relates each apparent weight to the geometry of the radii and the distances of the labelled points, concluding that the whole weight o rests on the poles s f and acts along the line s p f.
On this page
A load of 800 reduced along wheel, axle and handle
The 800 of e o weighs 700 at the circumference of wheel s, 100 at the circumference of wheel o, and 25 at the handle g, and at the poles s f more than its true natural weight, in the measure that o p enters into s o. By the 5th proposition the weight o presses on s the more above its natural weight as o p is less than n s, and by the 3rd it presses more on m than on s as p m is less than p s.
Lightness at the mover and load on the poles s f
By the 9th proposition, the gravity that s receives from weight o is the lighter to its mover as s n is greater than the semidiameter of the pole s, and the like for o f with semidiameter f. By the 7th, the weight o rests entirely on the poles s f and exerts its force along the line s p f.
Wheels, axle and handle drawn with their loads
The sheet is figured with wheels and axles bearing numeric loads (100, 700, 800) and a handle g, the mechanism that the accompanying propositions analyse. Two further figures on the left-hand page (241v) and a lettered figure on 238r accompany the numbered one but carry no transcribed text.