Fortification sketch lettered b b b
A structure in perspective — piers over an arched wall — keyed with the letters b b b
A rapid perspective sketch shows a built structure — upright piers or posts rising above a wall pierced by arches — that the note identifies as a fortification. Its points are keyed with the repeated letters b b b - b b b. Only these letter labels are given for the drawing.
On this page
Fortification keyed b b b
The note calls the drawing a fortification and lists its letters as b b b - b b b, marking corresponding points on the defensive structure.
Arched wall carrying upright piers
The structure is drawn in perspective as a wall pierced by arches and surmounted by a row of upright piers or posts.