That angle will offer the greatest resistance which is most acute, and the most obtuse will be the weakest.
[Footnote: The three smaller sketches accompany the text in the original, but the larger one is not directly connected with it. It is to be found on fol. 89a of the same Manuscript and there we read in a note, written underneath, coverchio della perdicha del castello (roof of the flagstaff of the castle),—Compare also Pl. XCIII, No. 1.]
Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.