Accidental weight, called force; balance diagrams
Force applied to weights does the office of gravity; pulley frames with a right angle at a
A pivotal note introduces 'accidental weight,' which Leonardo calls force: applied to weights, it performs the office of gravity. The surrounding rows of pulley frames and balances, drawn in black and red ink, are each labelled with their loads (16, 8, 4, 12), and one figure fixes the corner a as a right angle. The page belongs to his systematic study of how loads distribute across angled cords and pulleys.
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Accidental weight, called force
Here Leonardo begins to speak of the 'accidental weight,' which he names force; applied to weights it performs the office of gravity. It is the impressed action that adds to a body's own heaviness.
The corner a as a right angle
One frame is fixed by the condition that a will be a right angle, setting the geometry of the cords that share the load. The letter marks the vertex of the angled suspension.
Pulley frames labelled with their loads
Rows of pulley frames in black and red carry weights marked 16 8, 8 8 8, 10 10 10 and 16 4, showing how equal and unequal loads balance across a beam. The numbers record each suspension point's load.