Inscription: Inscribed in the negative: "40"; printed on mount, upper edge: "WAR DEPARTMENT [+ insignia]// Explorations West of the 100th Meridian. Expedition of 1871. Lieut. Geo. M. Wheeler, Com'd'g."; lower edge: "T. H. O'Sullivan, Phot.// GEOLOGICAL SERIES// WATER RHYOLITES, NEAR LOGAN SPRINGS, NEV.// No. 40".