[2] He moved at the age of 14 with his parents to Lawrence, Massachusetts, and apprenticed at the Essex Machine Company.

In 1852, he moved to Hartford, Connecticut, and worked at the Colt Armory.

At Colt, he met Francis A. Pratt who soon left to become superintendent at the Phoenix Iron Works and took Whitney with him.

The manufacturing of gun making machinery rapidly increased during the American Civil War.

[3] He died on August 5, 1920, in Poland Spring, Maine[3] and was interred at Cedar Hill Cemetery in Hartford, Connecticut.