Statics of Supports and Trussed Half-Vaults
Rule for seating supports on the strongest points; oblique gravity split into natural and accidental
The sheet sets down a principle of statics: supports (sostentacoli) should always rest on the greatest resistances of the supports beneath them, opposing the greatest weaknesses of the member they carry, and a support's strength should be directed toward the greatest weight of the thing borne. The accompanying note on roof trusses (capriate) explains that any heavy body of elongated form set obliquely divides its gravity into two parts — one tending toward the centre of the world, the other toward the direction of its slope — a distinction between accidental and natural gravity referred to 'the eighth book of weight'. Two cross-braced half-round frames are drawn at upper right; a sketch of a straining human figure and a red-chalk swirl of wavy lines, both untranscribed, occupy the left and lower parts of the sheet.
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Rule for seating supports on their strongest points
Supports should always be placed upon the greatest resistances of the lower supports and set against the greatest weaknesses of what they carry, so that the support's strength meets the greatest weight of the thing borne.
Oblique gravity split into natural and accidental
Any heavy body of long form set obliquely divides its gravity into two parts, one drawn toward the centre of the world and the other toward the side to which it leans. This obliquity separates accidental from natural gravity, as defined in the eighth book of weight.
Cross-braced trussed half-vaults
Two half-round frames braced with a lattice of diagonals are drawn at upper right, illustrating the roof trusses (capriate) whose statics the accompanying text discusses.
Sketch of a straining human figure
A rapidly drawn nude figure, bent as if under effort, appears left of centre, with a swirling red-chalk study of wavy lines below it. Neither drawing is covered by the transcribed notes.