Loring Coes
Loring Coes (April 22, 1812 – July 13, 1906) was an American inventor, industrialist, and Republican politician from Worcester, Massachusetts. He is best known for inventing the screw-type wrench, the tool commonly called the monkey wrench.
Coes served on Worcester’s City Council and Board of Aldermen, and he was a member of the Massachusetts House of Representatives in 1864–1865.
Born in Worcester, he married Harriet Newell Read of Attleboro on January 14, 1835. He and his brother Aury Gates Coes worked for Kimball and Fuller, a company that made woolen machinery. In 1836 they bought the business and formed the L. & A. G. Coes Company. A fire in October 1839 destroyed their factory, and the brothers moved to Springfield, where they worked as pattern makers in the foundry of Laurin Trask.
It was in Springfield that Loring Coes invented the screw wrench. Before this, wrenches like the English patent wrench and the Springfield/Merrick wrench required two hands to adjust. The new screw wrench could be adjusted with one hand. The Coes brothers sold a pattern for spinning machines to raise money to patent the wrench, and Loring Coes was granted the patent on April 16, 1841. After the patent, the L. & A. G. Coes company resumed manufacturing the wrench.
Coes died at his Worcester home on July 13, 1906 and was buried in Hope Cemetery, Worcester.
This page was last edited on 2 February 2026, at 08:08 (CET).