Unmeasured proportion grid: lettered segments only
Twelve line-segments lettered g-L, drawn without lengths
The folio lays out twelve lettered horizontal line-segments in a four-by-three frame - g, h, K; a, e, c; b, f, d; m, n, L - but assigns them no numeric lengths. It is the blank scaffold of a proportion diagram, the lettering set down before the measures were entered. The faint lines are in pencil retraced in pen, matching the run of proportion sheets around it.
On this page
The lettered but unmeasured framework
Twelve segments are lettered in a regular grid - g, h, K across the top, then a, e, c; b, f, d; and m, n, L below - with no lengths attached. The layout mirrors the measured tables on the neighbouring folios, showing the diagram's skeleton before its proportions are fixed.