Vault geometry, a glass-bell casting and river-crossing floats
Square- and barrel-vault proportions, a furnace and mould, and float-skins fitted to a saddle
A miscellany sheet whose upper half is filled with an array of squares carrying geometric compartment- and interlace-patterns, studies bound up with vaulting, set beside a note on the proportion of a square vault (a third of the chamber's diameter, credited to 'the German at the Duomo') and on a barrel vault that does not thrust its columns outward. Lower on the page are a furnace and mould for casting a glass bell and a saddle fitted with inflated skins for fording a river on horseback, with an oar tied behind the horse's neck. The sheet also carries a small sun-face sketch and later Spanish annotations that are not part of the transcription.
On this page
The rule of a square vault
A note beside a circle inscribed in a square gives the proportion of a square vault as a third of the diameter of its chamber. Leonardo credits the rule to 'the German' at the Cathedral (Duomo).
A barrel vault that does not thrust its columns out
Within one of the compartmented squares Leonardo sketches a scheme for a barrel vault, noting that it does not push the columns outward. It sits among the grid of geometric square studies.
Array of compartmented squares and interlace patterns
The top two-thirds of the sheet carry roughly a dozen squares filled with radiating diagonals, star-figures, circle-packings and interlace knots. These geometric compartment schemes relate to the vaulting notes below and are drawn faintly in leadpoint.
Casting a glass bell in a heated mould
To make a glass bell, Leonardo directs that the furnace be built in the usual way, as for bombards, and that the molten glass be poured into a red-hot mould. A furnace-and-mould apparatus with an arm is drawn at lower right.
A float-saddle for fording a river with an army
To cross a river with an army, inflated skins are joined to the saddle; because the striking hoof keeps a horse from swimming well, an oar is fastened behind its neck to help. The device answers the caption 'for crossing a river'.