The portraitist and inventor Bass Otis was born in East Bridgewater, Massachusetts, the son of a physician. He completed an apprenticeship as a scythe-maker and relocated to New York City around 1812, where he is thought to have worked in the studio of the noted portraitist John Wesley Jarvis (1781–1840). Otis moved to Philadelphia in 1812, joined the Society of Artists of the United States, and began to exhibit at the Pennsylvania Academy of the Fine Arts. He patented a device to aid artists, called the perspective protractor, in 1815. Otis was primarily a portraitist, but he also designed flags, engraved handbills, decorated coaches, painted advertising signs, and is credited with having been the first American lithographer. He was a member of the Franklin Institute of Science, and was elected an academician of the Pennsylvania Academy in 1824. Although Otis was active in several East Coast cities after 1837, he often returned to Philadelphia to paint portraits, and he died there at the age of seventy-seven.