Water Falling Through Air into a Pool
A program of study on cascades, their surfaces, and objects dragged under by the fall
Leonardo sets out a program for studying water that pours from a standing pool (pelago) out through the air and back down into water. He wants to record the surfaces that surround the falling water and their contacts, the motions of objects that fall together with it, and how floating things are pulled under when they drift toward the fall. A pen sketch at the upper right shows a curtain of water breaking into curling, foaming strands as it plunges.
On this page
Surfaces that surround water spilling from a pool into the air
Leonardo proposes to study the surfaces that enclose water as it pours from a standing pool out into the air, the places where those surfaces touch, and what the water does inside them. He frames it as a topic to be written up rather than a finished conclusion.
How floating objects are carried under by the plunging water
Objects floating on the still middle water sink once they drift from its center toward the fall, and are carried down with the plunging stream, which strikes the bottom of the pool and breaks into pieces. He observes that this middle water always submerges its own edges, because it sits at the center of all the currents reflected back up from the bottom.
Sketch of a foaming cascade
At the right a small pen drawing shows a sheet of water breaking apart into curling, feather-like strands of foam as it descends, illustrating the cascade the note describes.