Identifier: simsaduslondonam00leig (find matches)
Title: Simsadus: London; The American navy in Europe
Year: 1920 (1920s)
Authors: Leighton, John Langdon. (from old catalog)
Subjects: United States. Navy World War, 1914-1918
Publisher: New York, H. Holt and company
Contributing Library: The Library of Congress
Digitizing Sponsor: Sloan Foundation

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d up to this time had been of the contact* type, which means that the mine exploded when struck by a ship. On the outside of the mine there were four or five pins about eight Inches long; when one of these was struck, as by the side of a ship, it was driven Into the interior, the mine exploded. There were other types of contactmines, the detonating apparatus of which was of the same principle but differently carried out, in that in the place of pins, a bar on the top of the mine, would cause the explosion. Mines of this type would not bereally satisfactory in the proposed scheme, for too many would have to be laid. There were also those types which could be exploded from the shore by electricity, but these also would not answer thepurpose In such a broad area. What was wanted was a mine whose effective radius, or radius of danger, would be comparatively large. When America declared War on Germany, many inventions to be used against the submarine began to pour Into the Navy Department. Among these
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Title: USN 404 A "fleet" of mine

THE NORTHERN MINE BARRAGE 71 was the handiwork of one Mr. Ralph C. Brown, of Winchester, Mass.; his invention was exactly the sort of mine which was wanted for this Northern Mine Barrage. The principle was this: Attached to the mine were four or five very fine wires about 50 yards long; these wires were light enough and had sufficient buoyancy to keep them from sinking andso remained extended beneath the water, stretching with the current or in all directions at the same depth at which the mine was placed. Any large steel object, such as a ship, coming in contact with these wires, through the agency of an electric battery In the mine, would set an electric current in motion, which would explode the mine. Too much credit can never be given Mr. Brown for this invention, for it made the Northern Mine Barrage possible. When the idea of laying a barrage of mines from Scotland to Norway was taken up seriously in November, 1917, it was opposed in various circles, for some regarded it

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