80-G-707441:  Deep Sea Diving School, Naval Gun Factory, Washington, D.C.  Pressure tanks are used by the divers to simulate depths desired.  In this stage of training, each student makes dives to a simulated depth of 300 feet, released February 3, 1950.     U.S. Navy Photograph, now in the collections of the National Archives.  (2016/06/14).
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