These photos (above and below) show the stamp mill for the Sheldon & Columbian Mining Company in Houghton. This was located somewhere between where Michigan Tech and downtown Houghton are today. In the image above, you can see the exhaust from the steam powered stamps.
I am quite sure this is the incline for the Pewabic Mine, used to deliver mine rock from the operations on top of Quincy Hill with the stamp mill down at the Portage Canal.
The Franklin Mining Company Stamp Mill, located somewhere east of the current Portage lift bridge.
Two images of the Franklin Mine incline. This photo gave statistics of: Length of incline 2200 ft. Top of incline 600 ft. above level of Portage Lake and steepest grade 30 degrees.