Definitions of the plumb-line, with circle-in-square figures
Verso of the composite sheet: the 'appendiculo' restated six times, beside inscribed-circle diagrams.
This verso of the composite sheet is dominated by a series of restated definitions of the 'appendiculo' — the plumb-line or suspending thread that hangs a small weight in the air along the line toward the centre of the world. Leonardo rephrases the definition six times, each time refining how the thread's fixed upper end holds the weight at its opposite end. The mounted panels also bear faint figures of circles inscribed in squares along with small sketches; the editorial note records that two of the three original strips were blank before restoration, with other sheets once glued over them.
On this page
Six definitions of the appendiculo (plumb-line)
The appendiculo is a straight material line directed to the centre of the world, to whose lower part a small weight is joined, holding it suspended in the air. It is the straightness of a thread that, fixed at its upper end, suspends a small weight at the opposite end. Leonardo restates this several times, finally defining it as the thread that joins with the central line of the heavy body suspended from it.
Circles inscribed in squares
A grid of figures showing circles set within squares, drawn in one of the mounted panels. No transcription for these figures is included in the bundle, so they are noted here from the drawing alone; further untranscribed marks are present on the strip.