St. Anthony Falls apron and the 3rd Avenue Bridge on the Mississippi River in Minneapolis, Minnesota, as seen from the west bank of the river. The collapse of the Hennepin Island tunnel in 1869 brought about the construction of a curtain wall and protective apron apron, concrete structures that served to stabilize the falls. This image is by Arthur Adams, Minneapolis high school teacher, local historian, and photographer. Adams traveled throughout Minnesota, taking photographs to augment his lectures. His studio was located at 3648 Lyndale Avenue South in Minneapolis.