Surveying Levels, Wall-Piling and an Arched Gallery Mouth
A level for barbicans, a plumb level, water-boots, piling into a wall, and a stepped arched outlet.
The upper sketches present surveying instruments: a level for barbicans, a level for setting perpendicular lines, and a pair of water-boots (waders). Lower notes and drawings cover engineering details, one showing that piles are driven only as far as the middle of the wall beneath, and a larger perspective sketch of a gallery mouth with a stepped descent through little arches whose opening is to be four braccia.
On this page
Level for barbicans
A leveling instrument labelled as a level for barbicans (defensive outworks), drawn among the surveying tools at the upper right of the sheet.
Level for setting perpendicular lines
A second instrument, a level for laying out perpendicular lines, shown as an elongated plumb-frame beside the first.
Piles driven to the middle of the wall below
A wall-and-piles diagram, annotated that the piles are to be set only as far as the middle of the wall beneath them.
Stepped gallery mouth with little arches, span 4 braccia
A perspective sketch of a gallery outlet with a stepped descent through small arches, noted that the opening of the little arches will be four braccia.