Rick,
I found this information about the old picture, but I don't know where it's from (it's from a word document I have and no author is mentioned...so the reliability isn't 100%!):
Underneath the old picture you posted (which is also on my word document) is written:
"WWII Army mine-planting crew hauls up a seaweed-covered buoyant mine. Each mine carried 800-pounds of TNT and was connected by electric cable to a shore-based detonating station. When a vessel struck a mine, an impact-sensitive device in each mine sounded the alarm in the control bunker. The order could then be given to detonate the mine and blow up the vessel which hit it.WWII Army mine-planting crew hauls up a seaweed-covered buoyant mine. Each mine carried 800-pounds of TNT and was connected by electric cable to a shore-based detonating station. When a vessel struck a mine, an impact-sensitive device in each mine sounded the alarm in the control bunker. The order could then be given to detonate the mine and blow up the vessel which hit it."
In the documents is also written:
"
Background:
In 1891, an experimental mine field was planted in the Potomac River near Fort Washington, just south of Washington, D.C. The mine control room was casemated and improved in 1899. In 1898, during the Spanish-American War, the U.S. Engineers attempted to develop a minefield for the New York harbor, but the attempt failed due to the poor condition of the equipment and a complete lack of technical knowledge concerning the matter.
This poor situation continued through World War I and the U.S. Army was unable to plant any mines in the defense of the United States. The U.S. Army Mine Planter Service was established within the Coast Artillery Corps in July of 1918.
In 1931, the U.S. Army moved it's development and maintenance work from Fort Totten, NY, to the Submarine Mine Depot at Fort Monroe, VA. In 1939, a reliable controlled submarine mine system had been developed, but the U.S. had fallen far behind the British and Germans in mine technology. In 1941, the Army finally had the material, adequate facilities, and trained personnel in position at the local mine depots along America's coasts.
On December 7, 1941, the U.S. Army had approximately 5,000 moored, controlled mines in stock and 1,200 mines in defensive minefield projects had already been planted. In early 1942, all defensive minefields were completed in San Francisco, Portland, Boston, Narragansett Bay, New York, Chesapeake Bay, Portsmouth, and Cristobal and Balboa (located on each side of the Panama Canal).
Fields of both shore-controlled mines and some contact mines were planted near San Francisco during the late 1930s and early 1940s, being finished after America entered World War II on December 7, 1941. By the end of the war in 1945 the harbor was protected by 37 mine groups with 13 mines in each group, or 481 mines. But World War II, which brought harbor mine defense to its highest state or perfection, also spelled its doom, for air power demonstrated so effectively in that war left both coast artillery and shore-controlled under water mines obsolete in American defense."
I have some pictures about the "Submarine mine system M3 -buoyant) dated 1944 (see attached pics).
If we assume that the M3 is a future version of the mines you showed, the pictures could be a M1 or M2 version...it's just an assumption!
Greetz,
Stef
