Experiments on water pouring from vessels and apertures
Floating seeds to gauge surface flow, comparing nozzles, a sieve-bottom and a millet analogy
Six linked experiments, each with its own vessel-diagram, probe how water leaves a container. Floating equal grass-seeds in a ring around the outlet reveals which part of the surface moves fastest toward it; a two-nozzle section asks which spout, upper or lower, strikes its target harder; a sieve-bottomed vessel tests which of many equal holes pours most in equal time. Further notes examine the graded pressure across a column of standing water, propose using free-flowing millet or fine sand as a discontinuous stand-in for continuous water (invoking the 'license of mathematicians' who divide continuous time into degrees), and consider which water, falling perpendicular to its outlet, is readiest to move.
On this page
Floating seeds to find the fastest surface water
With the outlet set near the water's surface, equal floating grass-seeds are placed in a circle equidistant from the outlet at r m f; the first seed to reach the mouth shows which part of the surface moves fastest. Then the water is stopped and the circle observed.
Which spout, a or b, strikes harder
In the time the upper pipe a pours one quantity of water, the lower pipe b pours three; it is asked which delivers the greater impact on its target. The impact is to be weighed at an equal distance from each outlet.
A sieve-bottomed vessel: which hole pours most
A vessel pierced with equal holes like a sieve is tested by unstopping one hole at a time and weighing its output over a fall of one braccio, then re-stopping it. Fresh water must replenish the pouring vessel without impact, and the receiving vessel must be kept separate so the weight of water stays constant.
Graded pressure across a column of water
In a vessel of equal width and height, the width of the water divided into degrees a b c d e f n m shows that each part presses to level itself. If the vessel's walls were suddenly opened, every part would flee from its central perpendicular line, which line would be the last to sink.
Millet as a stand-in for continuous water
Slippery, fine millet is offered as an experimental substitute for water: stopping and unstopping the holes shows whether the millet's upper surface lowers just above the outlet. To the objection that water is continuous while millet is discontinuous, Leonardo claims the mathematicians' license of treating a continuous quantity (time) as divided into discrete degrees.
Water falling perpendicular to its outlet
A fragmentary closing note argues that the water pouring along a perpendicular line is always the part standing perpendicular above the vessel's hole, and that once the support is removed the faster water has sooner entered the place of the outlet. This holds only for waters free of impact from other water re-entering.