 In addition to the Edinburgh sets, more sets were authorized by Britannica to the London publishers Simpkin, Marshall and Company, and to Little, Brown and Company of Boston.Since Macvey Napier died in 1847, Adam Black selected for its editor Dr. Thomas Stewart Traill, a professor of medical jurisprudence at Edinburgh University.When Dr. Traill fell ill, he was assisted by a young Scottish philosopher, John Downes.