United States E-class submarine

Abstract is: The E-class submarines were a class of two United States Navy submarines, built by the Fore River Shipbuilding Company of Quincy, Massachusetts, under a subcontract from the Electric Boat Company. They were used as coastal and harbor defense submarines prior to World War I. When hostilities broke out, the E class were mostly used as training boats; however, E-1 operated on war patrols based in the Azores. During this time, the need for an improved permanent bridge structure was discovered; the temporary piping-and-canvas bridges were inadequate in the North Atlantic.