Why a Man Pulls More Downward than Upward
Two figures hauling a load, with the leg reckoned at a quarter of the body's weight
A double figure of a man hauling on ropes anchors a study of the mechanics of pulling. Leonardo gives three reasons why a man can pull more weight downward than upward: he throws more of his own weight beyond his central line, he plants his whole foot on that line, and he does not slip. A separate note reckons the leg, up to the socket of the thigh, as one quarter of the whole weight of the man.
On this page
Three reasons a man pulls more downward than upward
A man pulls more weight downward than upward, Leonardo argues, for three reasons: first, he casts more of his own weight beyond his central line; second, he sets his whole foot on that central line; and third, he does not slip with his feet. The paired hauling figures illustrate the shifting balance and stance.
The leg as one quarter of the body's weight
A brief note fixes the weight of the leg, taken up to the socket of the thigh, at one quarter of the whole weight of the man. The proportion feeds the study of how a body distributes its mass when pulling.