An act of Congress in July 1918 established the Army Mine Planter Service as part of the Coast Artillery Corps, designating warrant officers to serve as masters, mates, chief engineers and assistant engineers of the mine-planting vessels. They served with distinction in this hazardous field through both World Wars and other conflicts protecting America’s coastal cities and seaports. The command "Let Go!" was shouted to the men to release another mine into the watery depths.