 The following year he was offered a position as a lecturer at Harvard Law School , which became a full professorship in 1856 . The seat had previously been occupied by Judge Edward G. Loring , who Harvard 's Overseers refused to retain after he ruled that Burns be returned to slavery . For the next twenty years , Washburn served as one of three dominant figures ( along with Theophilus Parsons and Joel Parker ) in shaping the law school 's practices and curriculum . Legal historian Charles Warren wrote of the three , " Parker was the great lawyer ; Parsons the great teacher ; and Washburn , the great man . " The three men established a collegial and open learning environment at the law school . Washburn produced a significant number of legal treatises and books during his Harvard tenure ; his Treatise on the American Law of Real Property formed the basis for Harvard 's courses and later textbooks on the subject for the next century . His interests in history and the law were <unk> in these years , with a number of his publications covering aspects of both subjects . 
