Submarine signals
ATLAS-Werke, at the time Norddeutsche Maschinen und Armaturenfabrik, of Germany also manufactured the equipment under license largely for the European market.
The signals were usually associated with a lightvessel, a bell buoy or hung on a tripod frame on the sea floor connected to a shore stations by cable.
Lucian I. Blake in association with the United States Lighthouse Service did similar work in 1883 using a submerged bell with the explicit purpose of using sound as an aid to navigation.
Reception problems related to ship noise were partially solved when A. J. Munday, who had worked with Dr. Elisha Gray on signaling by underwater bells to include actual messages, found that a microphone placed in a metal box filled with water and attached to a ship's skin from inside allowed clear reception.
Canadian experiments showed the practicality of determining direction by comparison of the reception by two receivers mounted on each side of a vessel's bow.
The company developed, patented and began manufacturing electromechanical bell signals and shipboard receivers based on previous research, introducing the world's first electronic underwater acoustic navigation aid in 1901.
[2] The British Admiralty and Trinity House and, in Germany, the North German Lloyd Steamship Company took more immediate notice of the potential and became pioneers in implementation both at signal stations and as shipboard receivers.
By using the submarine signals of the entrance lightvessel the ship was able to enter the fog clear harbor to discharge passengers and cargo.
The tests were successful, with the Admiralty recommending their use as a coastal navigation aid with notes on the possible ship-to-ship use to warn and establish direction of another ship in fog.
[13] Experience of U.S. Navy battleships in fog off Nantucket Shoals proved the fleet could, under reduced speed, safely navigate and maintain formation by using the signals.
The U.S. lighthouse authorities were by the summer of 1906 installing signals, specifically at lightvessels stationed at Boston, Pollock Rip, Nantucket, Fire Island, and Sandy Hook.
[16] Extension into the Great Lakes revealed a problem with the forepeak receiver installation for seagoing ships operated in light condition in fresh water.
[19] The American Bureau of Shipping included whether a vessel was equipped with submarine signal apparatus as a part of the registry information along with wireless.
[28] The company acted quickly to replace the bells with the transducers and began working on their use in submarine telegraphy, but it was slow to recognize or take advantage of the sonic distance measurement of interest to Fessenden so that others took the lead in SOund NAvigation Ranging, now generally simply known as sonar.
Despite Fessenden's demonstration in June 1914 of the effectiveness of his device in telegraphy, that aspect faded and the "sensing" potential, first crudely applied to locating icebergs, became critical with World War I and submarine warfare.
Harold J. W. Fay of Submarine Signal Company was invited to meet with the Chief, Bureau of Steam Engineering 20 March 1917 to discuss establishing an acoustical research station at East Point, Nahant, Massachusetts.
Commander Clyde Stanley McDowell was secretary of the board and later filled the same function at the Naval Experimental Station, New London, Connecticut.
The laboratory, a cluster of buildings behind guarded security fencing, was where "submarine signals" research entered the new field of anti-submarine acoustics.
