The drawing below is from Gustave Eiffel's book describing the tower that bears his name. There are 53 of them in total.
Plate VI. Supports metal supports on masonry. Hydraulic cylinders. Pumps
The sixth plate is interesting in that it describes the setting of the metal part on the masonry. It is the support of the crossbowmen, whose description is very complete. This is the first study of metal parts of the Eiffel Tower, those of the lowest part. Curiously it is also on this board that are drawn the pumps and hydraulic cylinders that were used to adjust the batteries, when setting up the first floor.
See also:
