A leaf turning in a current; a water wheel struck by falling water
An autumn experiment with drifting leaves, and whether a wheel's blow adds to weight
Three notes with sketches. The first proposes studying how a leaf tumbles along different lines through the depth and width of a stream, driven by the water's oblique and whirling courses, an experiment to be run in autumn with fallen tree-leaves in clear running water. Beside it a row of five small objects 'of various shapes' is drawn as the test-bodies. The third note, next to a sketch of a bucket wheel (a b o m), asks whether water striking the buckets should be counted merely as its weight or as weight plus the power of its impact; if the latter, the wheel would raise water higher on the far side than the falling water itself, since the blow is not weight but sets in motion a power almost equal to itself.
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A leaf tumbling along oblique and whirling lines of a stream
A leaf turns along various lines, high and low, through the depth and breadth of the water, driven by its oblique and whirling courses. Objects of various shapes should be set in the current and tested in autumn with tree-leaves carried from surface to bottom of clear running water.
Water wheel struck on its buckets (a b o m)
Water a b strikes the buckets of the wheel while other water already sits as weight in the buckets on the struck side. Leonardo poses the design question of how the striking water should be reckoned in driving the wheel.
Does the blow of falling water add to its weight?
Leonardo asks whether the striking water counts only as weight or as a greater quantity with the power of percussion added. If the latter, the wheel would raise water higher on the opposite side than the water that falls, since the blow is not weight but moves a power of weight almost equal to itself.