In Britain the echo-ranging equipment finally developed 

 took its name from the initials of the committee and became 

 known as ASDIC The American name of "sonar," not adopted 

 until 1943j, is generated from the words; SOund, Navigation 

 and Ranging, 



Naval Research Laboratory. 



Sonar in the United States was developed in the face of 

 great handicaps „ The Government research work which had been 

 started in the U.S Naval Experiment Station at New London was 

 transferred with reduced personnel to the Naval Engineering 

 Experiment Station at Annapolis, Maryland,, pending completion 

 of the Naval Research Laboratory at Anacostia, D. C 



The work was costly and funds for scientific research in 

 the military field were scarce The expense had to be born by 

 the Navy, and the Navy, in the era of the Washington Naval 

 conference s was having financial difficulties „ If it were pos- 

 sible and popular to sink battleships, it was even easier to 

 wreck a research program,, The underwater sound program was 

 starved for funds c Scientists had to be imbued with both 

 patience and patriotism to put up with the wages the Civil 

 Service scale allowed for first-rank talent „ But the Navy De- 

 partment Bureau of Engineerings, which in 1940 became part of 

 the present Bureau of Ships 9 went energetically , if slowly, 

 ahead,, 



In 19 23 the work of the Naval Research Laboratory was 

 transferred from Annapolis to the new station at Anacostia,, 

 This laboratory and the Submarine Signal Company were the only 

 two organizations left in the field,, The research program 

 attempted both to improve the multi-spot listening device and 

 to develop further the possibilities of echo-ranging 



The first types of echo-ranging gear to be tried out 

 followed the principle demonstrated by Langevin,, which was 

 used in the experimental model XL equipment developed by the 

 Naval Research Laboratory,, Exhaustive tests at sea in 1928 

 showed that the equipment could give reliable results at 

 ranges up to approximately 1200 yards Such ranges obviously 

 were inadequate for purposes of search, but the new equipment 

 greatly strengthened the attack once listening contact was 

 made with the target , Using the XL as a prototype a few model 

 QA echo-ranging devices were installed on surface ships and 

 experience with them confirmed the experimental test results , 



7 



