Exposition Herald American Christian Missionary 1911 Boston Mass. Expo magazine(Old Books, Early 20th Century, Americana, Religion, Christianity, Periodicals, Missionary Work, ). The Exposition Herald: America's First Great Missionary Exposition. April 24 May 20 1911. Published 1911, Boston by the World in Boston. c. 60 pages. Text in English. Illustrated throughout. Abundant period advertising. There are variant issues of this magazine by month with varying contents. Publisher's pictorial color lithographed paper wrappers,