Known in Edinburgh as a debt-ridden eccentric, between 1776 and 1784 Tytler almost single-handedly revised the original edition of Encyclopædia Britannica, enlarging it from three to ten volumes, including historical and biographical material for the first time. He was one of the first men in Britain to attempt a balloon ascension (August 1784). A political radical, he was forced to emigrate in 1792 because a handbill he had printed was deemed seditious. Tytler ended his days as a newspaper publisher in the United States.