Photographed in relaxed shirt-sleeve order with hats set aside, this group of U.S. Army servicemen represents a unit stationed at Mather Field, California, during World War I. The wooden barracks visible in the background reflect the hastily built training cantonments common to American airfields of 1917-1918, when Mather Field served as a key West Coast site for training Air Service personnel. The informal dress -- shirts without coats, hats removed -- offers a more candid counterpart to the formal dress portraits typically taken of military units during the period. Project: 218714