In 1873 Mr. Baker was issued a patent for his invention from the United States Patent & Trademark Office (USPTO). There were 3 documents on file for this patent. The drawing specification sheet of the patent has been reproduced from original USPTO documents and printed onto parchment paper. This print is sized and ready to install into an 8" x 10" frame. The additional sheets included are printed on 5.50" x 8.50" parchment paper. These accompanying documents describe the scope of this invention in formal terms. The following is an actual excerpt from the patent…

       " Be it known that I, JOHN G. BAKER, of the city of Philadelphia Pennsylvania, have invented certain Improvements in Grinding- Mills, of which the following is a specification: The objects of my invention are, first, to securely retain the working parts of a hand grinding-mill within the casing, and to enable the same to be readily removed when necessary; and, second, to prevent waste of the material to be ground in its passage from the hopper to the space between the burrs"…