Cpl. Gilbert Thompson, Co. A, U. S. Engineer Battalion
Printer, Topographical Engineer, Postwar Founder of the National Geographic Society
Gilbert Thompson maintained a detailed journal of his wartime experiences with the U. S. Engineer Battalion. The volume is in the Manuscript Division of the Library of Congress and is on-line in its entirety at http://hdl.loc.gov/loc.mss/mss95752.01
Thompson wrote in his journal on August 23, 1864: "Rec'd my photograph of the Essayons Dramatic Club -- much pleased with it."
Gilbert Thompson wrote"The Engineer Battalion in the Civil War: A Contribution to the History of the United States Engineers," edited and re-published after his death in 1910 in the Occasional Papers Engineer School, United States Army, No. 44.