Friction of stacked weights, with an old woman's bust
A rule that doubled load doubles the drag, beside a chalk profile and a motto on beauty
The lower half carries pen and chalk diagrams of weights set one above another and side by side, marked with the numbers 2, 1, 100 and 2, 31, alongside a note that friction is of doubled effort in doubled weight. Above them, drawn in black chalk, is the bust of an aged figure in profile, gazing right. Beneath the head runs the motto that a beautiful mortal thing passes and does not endure.
On this page
Friction grows with the load: doubled weight, doubled drag
The stacked and side-by-side blocks, numbered 2, 1, 100 and 2, 31, illustrate a rule of friction. Leonardo states that 'friction is made of doubled effort in doubled weight', that is, drag increases in step with the load pressing down. It sits among his repeated pocket studies of how weights resist being moved.
Chalk bust of an aged figure in profile
A black-chalk bust of an old figure occupies the top of the leaf, the head turned in profile with a lined, sunken face. It is one of Leonardo's characterful studies of age. The bundle labels it a bust of an old woman.
Motto: beautiful mortal things do not last
Written beneath the chalk bust is the line that a beautiful mortal thing passes and does not endure. The aphorism pairs pointedly with the study of an aged face. It is one of the moral tags Leonardo scattered through his notebooks.