Constructing the triangle of a triangular balance
A compass procedure for sizing an equilateral triangle to given weights
The main text is a step-by-step compass construction for finding the true size of the equilateral triangle that forms a triangular balance, using a base line p o, perpendiculars b p and c o, and points m, n, S and r to fix the intersections. A triangle-inscribed-in-a-circle diagram with two small hanging weights sits beside the writing, and jointed mechanical linkages are sketched above. The Ambrosiana catalogue ties the sheet to instruments and machines and to calculating a device's power.
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Compass construction of the balance triangle
Starting from the line p o that carries the given weights, one raises the perpendiculars b p and c o, then swings arcs from m and n to find where the curved lines meet the line p b. Fixing the compass there yields the line n m and an equilateral triangle sized to the proposed weights, with corrections described if the intersection falls short of or beyond p b.
Triangular balance with hanging weights
The diagram shows a triangle set within a circle, with two small boxes suspended below as weights, illustrating the balance whose triangle the text sizes to suit the loads it must carry.
Jointed linkages above
The upper part of the sheet carries several articulated, jointed linkages drawn in pen, related to the mechanical studies of the facing side of the leaf.