American inventor and clock maker whose products enjoyed widespread popularity in the mid-19th century.

Learning the carpenter's trade early in life, Jerome was employed as a case maker in 1816 by Eli Terry (Terry, Eli), a clock maker at Plymouth, Conn. Later Jerome started his own business, selling clocks with his cases fitted with movements supplied by other makers. The bronze looking-glass clock case he designed in 1827 became especially popular; he then formed a company that soon became the leader in clock production, with the main plant located at Bristol, Conn.

About 1838 Jerome invented the one-day brass movement, an improvement in durability over the wood movement in a clock. Applying mass-production techniques, Jerome flooded the United States with low-priced brass clocks. His clocks quickly spread to Europe and so astonished the English that “Yankee ingenuity” became a byword.

In the 1850s Jerome became associated with unethical businessmen, and his company failed in 1855; he died in relative poverty.