Passage made under water, drained by a pump
A hollow behind a spiral staircase from which a pump draws off water; a hinged frame below.
The upper drawing shows the plan and section of a passage built under water, four braccia high and two wide, whose water can be admitted or drawn off at the will of its operator. Behind a spiral staircase a hollow is formed from which a pump removes any water that drains into it from the excavation. A separate elongated hinged frame or mechanism is sketched in the lower strip of the sheet, not covered by the transcribed note.
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Draining the excavation with a pump behind the spiral stair
Behind the spiral staircase a certain hollow is formed. By means of a pump, all the water that descends from the excavation into that hollow can be drawn off, so the passage can be kept dry.
Passage made under the water, 4 by 2 braccia
A passage is made under the water, four braccia high and two wide. Its water can be let in and taken out at the will of the operator who tends it.
Elongated hinged frame in the lower strip
A long narrow frame or mechanism is drawn as a separate device across the lower band of the sheet, with a sliding block at one end and pierced fittings along its length. The transcribed note does not describe it.