Thomas Earle [1737-1819] of Leicester, MA, was the cousin of the American painter Ralph Earl. The different spellings of the surname between the cousins can be traced indirectly to Thomas' occupation as a gunsmith. According to family tradition, George Washington ordered a gun made by Thomas, and in seeing the spelling of the name inscribed on the weapon is reputed to have said, "Mr. Earle, your name is not correctly spelled. E-a-r-l is a title of nobility; you should add an e to it." (Pliny Earle, the Earle Family: Ralph Earle and His Descendants (Worcester, MA: 1888), 57). When Ralph Earl visited his hometown of Leicester in 1880, he painted a portrait of his cousin, which is now in the collection of the National Gallery of Art (1947.17.42).
Earle, Pliny. The Earle Family: Ralphe Earle and His Descendants Worcester, MA, 1888: 57-58