210-J8 Front view of sounding apparatatus used to locate approaching aeroplanes. Barracks #66 Tours Aerodrome, France, May 18th, 1918.
Air Service, United States Army photograph
1918
Air Service, United States Army photograph, Gorrell's History of the American Expeditionary Forces Air Service, Series M Misceanelous, Volume 7 Titles for Still Pictures of Air Service Subjects and Photographs of Air Service Subjects  via <a rel="nofollow" class="external free" href="http://www.fold3.com">http://www.fold3.com</a>