The drawing below is from Gustave Eiffel's book describing the tower that bears his name. There are 53 of them in total.
VIII. Metal frame in elevation. Spacers, braces and floors
This plate concerns the metal part. Eiffel describes precisely the spacers of each section and the braces. The spacers are the diagonal bars, for each section. Bracing is a device designed to take wind loads back into the structure and descend to the ground along the rafters. This plan also shows the structure of the 3 floors.
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