Painter. His best-known painting numbers among American artists' earliest pictorial responses to studio practice and its theoretical underpinnings. Fresh, direct, and pictorially complex, The American School (Metropolitan Museum, 1765) evokes the art life of Benjamin West's circle in London. Although Pratt tried his hand at history painting and still life, his professional effort generally was limited to portraiture, reflecting the preference of the American market in his day. Even so, after twenty productive years before the Revolution, he eventually turned to other pursuits. A lifelong Philadelphian, Pratt learned his craft during an apprenticeship between 1749 and 1756 with his uncle, James Claypoole (1720–84), an artisan who also traded in art supplies and may have painted portraits (none conclusively identified). Until 1764 when he departed for London, Pratt worked primarily as a portrait painter in Philadelphia. Regarded as West's first American student, for the next two-and-a-half years Pratt worked informally with the slightly younger but better trained painter. Completed during this period, The American School depicts West, at left, and Pratt, seated before an easel at right, along with three unidentified young men. Their anonymity barely matters, for the painting subordinates individual identity to pictorial challenges and the absorbing pleasures of artistic creation. During the final year and a half of his stay in England, Pratt painted portraits in Bristol. After returning home in 1768, he portrayed clients in New York and Williamsburg, Virginia, as well as in Philadelphia. On a visit to Europe in 1770 he worked for some months in Ireland and England. From the mid-1770s, his activities in Philadelphia included teaching drawing, selling art supplies, and painting signs renowned for excellence in their day. Pratt's cousin James Claypoole Jr. (c. 1743–before 1815) became a more accomplished artist than his father, who presumably trained him also. Born, as his father had been, in Philadelphia, he was professionally active in that city from the early 1760s, primarily as a portraitist. Also a printmaker, he is known to have produced political cartoons. Intending to go to London for additional training, he left around 1769 but instead continued to practice his craft in Kingston, Jamaica and may never have returned.