Overbalancing wheels and the blow of a falling stick
Vaned wheels, a ball at a semicircle's lowest point, and the counting of clock hours
The sheet is filled with circular diagrams of wheels bearing curved vanes and spokes, a labelled semicircle a·m·n, a small seated figure at the left, and a toothed gear at the lower right. The notes treat mechanics: a ball (the centre of gravity of a liquid body) settling at the lowest point of a semicircle, and the blow of a stick m·n striking the pegs a, b or c to test which produces the greater motion in a wheel. A further passage imagines the hours of a clock counted aloud in unison by more than a thousand people at the same instant. Dense mirror-script beyond the transcribed blocks remains on the sheet.
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Ball settles at a semicircle's lowest point
The semicircle a·m·n cuts all twelve semicircles so that the perpendicular drawn at the cut falls between equal angles and touches the semicircle at its lowest part. In that lowest point the ball — the centre of gravity of any liquid body — comes to rest.
The blow of a stick as multiplication of weight
Recalling his seventh conclusion, Leonardo holds that a blow struck with a stick near the holding hand is more a multiplication of weight than the nature of a stroke, especially when the hand stays fixed. He proposes testing the stick m·n as it descends and strikes the pegs a, b or c to see which drives the wheel most.
Counting the hours of a clock in unison
One note fancies that a word spoken by one person could be echoed at the same instant by more than a thousand others who neither see nor hear him. These are likened to the hours counted by a clock, so that all who count them name the same number at the same moment.