In the second half of the 19th century Beirut joined Istanbul and Cairo as a city of major importance in the Muslim world's growth of scientific awareness. In this instance it was not Muslims who came directly into contact with western science, but Arab Christians inspired by a few exceptional American teachers and missionaries. The Americans had been preceded centuries earlier by French missionaries in the Levant. The Boston Board of Commissioners for Foreign Missions is the first American missionary reached Beirut in 1823. With its large Greek Orthodox population waiting to be saved, the city, though quite small at the time, was soon to become a chief center of American evangelism. The American missionaries had taken to the language with that same religious zeal exhibited by young Mormons today who in short time master the language of their destined country of mission work. Salim Bustani figured prominently in the American evangelist community.