Impetus and percussion in inverse proportion
A numeric scale of impact, with a note on land measures
The sheet carries a graduated quarter-circle arc with rays at upper right and two right-angled frame figures at left, beneath a short block of text. Leonardo tabulates an inverse relation between impetus and percussion: as degrees of impetus rise from 1 to 8, the degrees of percussion fall from 7 to 0. A separate note records land measures, defining the staioro 'a corda' as 1728 square braccia and the staioro 'a seme' as three of them.
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Eight degrees of impetus yield none of percussion
No degree of impetus gives 8 of percussion. One degree of the power of impetus gives 7 of the power of percussion; 2 give 6, 3 give 5, 4 give 4, 5 give 3, 6 give 2, 7 give 1, and 8 gives none: an inverse scale in which impetus and percussion sum to eight.
Land measures: the staioro 'a corda' and 'a seme'
The staioro 'a corda' equals 1728 square braccia by the measure of the tower, these braccia being smaller than the cloth-braccia by between a sixteenth and a seventeenth. The staioro 'a seme' is composed of three staiora 'a corda'.