Salt

#OTD The U.S. Constitution reads, "The Congress shall have power…to promote the progress of science and useful arts by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries…" Nancy Johnson took advantage of this sweet provision on September 9, 1843, who was issued patent #3254 for her hand-cranked ice cream maker and freezer machine. The patent read, "Be it known that I, NANCY M. JOHNSON of the city of Philadelphia and State of Pennsylvania, have invented a new and useful improvement in the Art of Producing Artificial Ices, and that the following [...]