118 MARINE SCIENCE 
The applied physics laboratory is one of many such organizations 
now existing for the purpose of providing the executive branch of the 
Federal Government, especially the Department of Defense and the 
Atomic Energy Commission, with the benefits of basic and applied 
research, conducted in a university atmosphere, where profit is not a 
motive. We are a small laboratory, having a total staff of about 125 
people, but with a high density of Ph. D. scientists, as befits a univer- 
sity. We are wholly concerned with the problems of the Bureau of 
Naval Weapons of the Navy Department; except for a brief period of 
ONR support about 10 years ago, it has always been thus. 
The laboratory began its existence in 1943 as part of the applied 
physics laboratory of Johns Hopkins University, whose name we bor- 
rowed and continued to use after separating from them as our pro- 
grams diverged. Our reason for organization was to solve a serious 
torpedo exploder deficiency existing at that time, when the war in 
the Pacific was at its peak. The Johns Hopkins group was actively 
engaged in proximity fuze work at the time, providing a fruitful 
technical basis for the torpedo work. We have been involved in 
underwater ordnance work ever since. 
During the war, the acoustic homing torpedo was born, and al- 
though the war ended before its influence was felt, torpedoes of this 
kind have received lively development to a present-day point of con- 
siderable sophistication. We can safely say that the acoustical prop- 
erties of the sea are the heart of nearly all present antisubmarine 
warfare systems. The laboratory has provided a great deal of instru- 
mentation for these antisubmarine warfare (ASW) weapons as a 
part of its tasks—in particular, the measuring apparatus and stand- 
ards against which to measure their performance. These include 
calibrated artificial acoustic targets, and, more recently, three- 
dimensional acoustic underwater tracking ranges which reveal in de- 
tail all aspects of weapon performance against submarines. The 
best known such range is operated in Dabob Bay, off Hood Canal, 
by the Naval Torpedo Station at Keyport, Wash.; it is in daily use, 
with a heavy workload stemming from many branches of the Gov- 
ernment, including the Bureau of Ships and the Atomic Energy Com- 
mission, as well as the Bureau of Naval Weapons. 
I think I can safely say that this little chunk of water out there 
in Dabob Bay is probably the most important single bit of water, 
as far as antisubmarine warfare is concerned, of any that exists in 
the free world today. I think this is an important consideration. 
The Cuatrrman. How deep is it there? 
Dr. Henvrerson. Approximately 600 feet deep, and over a consid- 
erable area, which makes it possible for us to work with most of our 
deeper weapons, as you can understand. 
A similar system was installed off San Clemente Island in Cali- 
fornia about a year ago, and this was preceded by an important range 
experiment conducted in the deep, quiet fiords of southeastern 
Alaska—Chatham Strait, the finest waters of all for these experi- 
ments—is the summer of 1959. 
The acoustic instrumentation described above, as well as other 
projects and studies concerned with weapons systems, has caused us © 
to face time and time again the uncertainties resulting from an in- 
complete knowledge of basic ocean properties. In order to meet the 
