File. (open access)

File.

Patent for a new and improved file. This design "consists in the improved construction and combination of parts of a file having its teeth cut to extend half-way across the face from each edge and at an angle to each other, and having a longitudinal groove in the middle of each face" (lines 22-27).
Date: November 2, 1886
Creator: Custer, George
System: The Portal to Texas History