A really interesting structure – First Quincy No. 2 shaft house (Wisconsin.)  Inside, iron ore would have been processed.  The rooflines follow the flow of ore down through the building.  Just like western American mines built on hillsides, they used gravity to move the ore through the crushing/screening operations.

This would be quite some challenge to make, and to get all the roof sections lined up.  Though the second tier up on the right hand side seems to have a different pitch from the other roofs – and this difference is not echoed on the left.