Hayes was born in
Windsor, Vt., Feb. 28, 1806. He was graduated from the Norwich military school in 1823, and studied chemistry under Prof.
James Freeman Dana at
Dartmouth, 1823–1826. Hayes was assistant professor of chemistry in the New Hampshire medical college, 1826–1828, and an expert chemist in Boston, Mass., 1828–1882. He was the discoverer of the organic
alkaloid sanguinaria; invented in 1838 a novel arrangement of steam boilers for the economical generation of steam: and first suggested the application of
oxides of iron in refining
pig-iron; and a process for the production of
saltpetre from
sodium nitrate by the action of
potassium hydroxide. Hayes was
state assayer of Massachusetts, and he received the honorary degree of M.D. from Dartmouth in 1846. He died in
Brookline, Mass., June 21, 1882. ==Publications==