He was born on February 15, 1827 in Woodstock, Vermont, United States, the son of Nathaniel M. and Euphemia (Nutting) Pratt. He was descended from the John Pratt who came from the southern part of England and settled in Dorchester, Massachussets, where he was made a freeman on May 4, 1632. When Francis was eight years old, his father, who was a leather merchant, moved to Lowell, Massachussets.
He obtained a common-school education in Lowell, Massachussets. While still in his teens he was apprenticed to a machinist.
Upon completing his apprenticeship in 1848, he entered the employ of the Gloucester (New Jersey) Machine Works, where he continued for four years, first as a journeyman machinist and afterwards as a contractor. In 1852 he entered the Colt armory at Hartford, Connecticut, and worked there two years. It was here he met his future partner, Amos Whitney, and after accepting the superintendency of the Phoenix Iron Works, Hartford, in 1854, he soon secured the transfer of Whitney to the same establishment, where they worked together until 1864.
Meanwhile, in 1860, Pratt and Whitney began doing machine work on their own account in their spare time, and in 1862 took a third person, Monroe Stannard, into partnership and enlarged their shop. By 1864 their business had grown to such extent that the two men gave up their positions at the Phoenix Iron Works, and in 1865 constructed the first building of the Pratt & Whitney firm.
In 1888 the company began the manufacture of the Hotchkiss revolving cannon for the United States Navy, as well as three-and six-pound rapid-fire guns, and in subsequent years, until the Hotchkiss gun was discontinued, turned out over four hundred of them. Pratt patented a number of machine tools, the most important being a machine for planing metal, August 17, 1869; a gearcutting machine, July 1, 1884; and a milling machine, July 28, 1885.
Pratt remained as president of his company until 1898. Thereafter, he served as consulting engineer to the organization until his retirement about two years prior to his death. He was an alderman of Hartford for several years and a director of a number of industrial corporations in New England. He died in Hartford, Connecticut.
Francis Ashbury Pratt was a pioneer and leading spirit in improvements in manufacture of machine tools, and tools for making guns and sewing machines. He was active in promoting the manufacture of interchangeable parts, a system now in universal use, inaugurating it in his own factory during the Civil War in the making of firearms. After the war Pratt introduced this system abroad, and his company manufactured practically all of the machinery for many of the armories of western Europe. He also patented a gearcutting machine, which was the first to permit the production of fine gear work.
He was a charter member of the American Society of Mechanical Engineers.
On October 31, 1850, he married Harriet E. Cole of Lowell. They had two children.
