He continued to paint portraits, among them those of several members of the royal family and numerous British and American celebrities. Between 1776 and 1815 he sent forty-three paintings to exhibitions of the Royal Academy, of which he was elected an associate member in the former year. His election to full membership occurred in 1783. The effort with which Copley labored over his compositions was exemplary, but at times it may have injured his health and disposition. "He has been represented to me by some," wrote Cunningham, "as a peevish and peremptory man while others describe him as mild and unassuming." Both descriptions probably fitted Copley depending on his mood: he might be nervous from overwork and worry or in a normal condition. His granddaughter, Mrs. Amory, recalls that he usually painted continuously from early morning until twilight. In the evening his wife or a daughter read English literature for his benefit. He took but little exercise–probably not enough for health. He would have liked to return to America but his professional routine prevented this. He was politically more liberal than were his relatives. He painted the Stars and Stripes over a ship in the background of Elkanah Watson's portrait on December 5, 1782, after listening to George III's speech formally acknowledging American independence. "He invited me into the studio," wrote Watson in his Journal, "and there, with a bold hand, a master's touch, and I believe an American heart, attached to the ship the Stars and Stripes; this was, I imagine, the first American flag hoisted in Old England." Copley's contacts with New England people continued to be many. He painted portraits of John Adams, John Quincy Adams, and other Bostonians who visited England. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1791. His daughter Elizabeth was married in August 1800 to Gardiner Greene of Boston, a wealthy gentleman whose descendants preserved much of the correspondence of the Copley family. Prior to this marriage of his daughter, Copley had sold his Beacon Hill estate to a syndicate of speculators headed by Dr. Benjamin Joy. He felt himself victimized when he learned that the purchasers knew of a project of building the Massachusetts State House at the top of the hill, and he sent his son John Singleton Copley, Jr., then at the beginning of his brilliant legal career, to Boston in 1796 seeking to annul the arrangement. The letters which the future Lord Chancellor wrote during his visit to the United States are interesting reading but his quest was unsuccessful.