So... check out @Private Lugnutz's method for finding patents. I take a more circuitous route than he does, using Google to start the search.
I should probably edit that. I always try Google and/or Google Books first. In fact, if you Google "Sagendorph patent December 28, 1886," it finds the patent. My instructions are for real stumpers. Patents that Google or Google Books won't find by date alone, by date and name, or by date and name of manufacturer.
Looks like it was designed for cutting corrugated sheet metal without flattening the corrugations.
Dude was into roofing. He patented a nail-less roofing system four years earlier. See
US255087, granted March 14, 1882.