Curved Water-Lines and a Ship's Displacement
Water surfaces curve, a wave follows the air, and a ship displaces its weight
A red-chalk and pen leaf on the geometry and force of water in motion, with a diagram of water-lines and a small figure of a ship (n, n, a). Leonardo states that the free motion of water's upper part forms no true angles except at the point of percussion, and that all its upper lineaments are curved. He notes that a wave follows the motion of the air that touches it, while anything caught between air and wave follows the motion of neither. Finally he sets down a buoyancy principle: the water missing from the place a ship occupies weighs as much as the whole vessel that drives it out.
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Upper water-lines curve; angles form only at the impact
The free motion made by the upper part of the water forms angles of no kind except in the percussion. All the upper lineaments produced by the motion of the water, Leonardo writes, are curved.
A wave follows the air that touches it
The wave follows the motion of the air that touches it. Anything enclosed between the air and the wave, however, follows the motion of neither the one nor the other.
A ship displaces its own weight of water
The water wanting in the place a ship occupies weighs as much as all the rest of the vessel that drives it out. The principle is set beside a small figure of a ship, marked n, n, a.