Compounded and separated proportion
A single figure of labelled segments held to serve two conclusions of ratio theory
The note is headed 'Congiunta e disgiunta' — proportion compounded and separated — and belongs to Leonardo's Euclidean study of ratios in Manuscript K. Labelled segments give the magnitudes e 8, a 12, b 4, c 6 and d 3, and a line of text states that the figure above serves for two conclusions, namely that ab is to b alone as ed is to d alone. Four lines of writing at the upper left are in Leonardo's mirror script; a library stamp appears at the lower right. The figures are pencil gone over in pen.
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Compounded and separated ratios
Headed 'Congiunta e disgiunta,' the page treats proportion both compounded and separated. The magnitudes e 8, a 12, b 4, c 6 and d 3 are set out on labelled segments, and Leonardo notes that the figure above serves for two conclusions.
'ab is to b alone as ed is to d alone'
A verbal statement of the proportion accompanies the drawing: the whole ab is to b by itself as ed is to d by itself, expressing the separated ratio in words.