In 1860, while still working at the Phoenix Iron Works, Pratt and Whitney formed the Pratt & Whitney company. Their first product was a thread winder for the Willimantic Linen Company. They went on to manufacture machine tools for the manufacture of guns, sewing machines, bicycles and typewriters. The manufacturing of gun making machinery rapidly increased during the American Civil War.[4]
In 1893, Whitney was made vice-president of the company and worked as president from 1898 to 1901. The company was acquired by the Niles-Bement-Pond Company and Whitney remained as one of the directors. He also worked as president and director of the Gray Telephone Pay Station Company, director of the Pratt & Cady Co., director in the Co-operative Savings Bank[1] and as treasurer of Whitney Manufacturing Company which was organized by his son Clarence.[3]