How Falling Things Break Apart: Beams, Stones, and Grain
Continuous, discontinuous, and neutral falling bodies; the hopper experiment
Leonardo classifies falling matter into three kinds: continuous quantities such as staves, beams and liquids (which become discontinuous when the fall is long), discontinuous ones such as stones, and neutral ones such as millet or sand poured from a hopper. He proposes testing the hopper at a great height to see how the once-united stream loses its unity and changes density before it strikes below. A closing note observes that if the air were of uniform density at every height, descending bodies would gain equal degrees of velocity at every degree of motion. A small untranscribed pen sketch of concentric arcs, representing the eddying wave of air, sits in the lower part of the page.
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Continuous, discontinuous, and neutral falling quantities
Some falling things are continuous, such as staves, beams and liquids; others discontinuous, such as separated stones; and others neutral, such as millet or sand poured from a hopper. Leonardo urges proving this at a great height and noting the difference between the stream's unity as it leaves the hopper and its density when it strikes below.
Uniform air would give equal gains of velocity
If the air had the same density at every part of its height, then descending bodies would acquire equal degrees of velocity at every degree of motion. The variation of real fall is therefore tied to the changing resistance of the air.
A united mass reaches the ground as tiny droplets
The quantity that was united and powerful up above comes to reach the ground broken into tiny droplets. The prolonged descent turns a once-continuous liquid into a scattered, discontinuous fall.
Untranscribed sketch of eddying air
In the lower portion of the page a small pen sketch of concentric curved strokes represents the eddying wave of air raised by a falling body. It is drawn rather than described in the transcribed text.