The drawing below is from Gustave Eiffel's book describing the tower that bears his name. There are 53 of them in total.
Plate II. Type of soil. Clearing in the open air. Compressed air cuttings. Concrete masonry
This second plate concerns the excavations and the nature of the grounds. On the left side there is the nature of the soil at the level of the excavations, ie the distribution of the soil type according to the depth. This is complemented by the design of the wells, which also gives the nature of the soil to a depth greater than that of the excavations. The right side shows the excavations as they are, with the concrete blocks. Everything is on the side, of course, very precisely. As there are 4 pillars, the plan shows 8 diagrams, for each pillar there is the top view and the one in section.