The First Patent Grant in the
The patent grant you see reproduced below was the first one issued by the United States, to Samuel Hopkins of
Pittsford, Vermont in 1790. Two other patents were granted that year: one for
a special process of making candles and one for improved flour milling
machinery. The Hopkins patent was for an "Improvement, not known before
such Discovery, in the making of Pot ash and Pearl ash by a new apparatus and
Process", and was granted for a term of fourteen years.
The name potash refers to several potassium
salts, mild alkalis, which were derived from the ashes of timber or other
plants. It was also known in a caustic form when mixed with lime. In reacting
with fats or oils, potash produced a soft soap. It was an essential ingredient
in the manufacture of glass, alum (salts of aluminum--used chiefly in
medicine), and saltpeter (an important ingredient in gun powder). Potash also
played an important role in bleaching, mining, metallurgy, and other
industrial interests. Its many applications served as an indication of the
emerging chemical industry in the nineteenth century.
In the summer of 1956, the Vermont Historic
Sites Commission erected a marker at the former residence of Samuel Hopkins.
The original patent granted to him still exists in the collections of the
Chicago Historical Society.