important. Take the case of some outboard submarine equipment. 

 If it is mounted outside on the hull beiow water level, the measur- 

 ing "readout" will probably not have to be greater than from 28° - 

 90° F. for just under the ice and for shallow lagoons and the Red 

 Sea. But what about instrument protection during drydocking at 

 Pearl Harbor? The sun beats down there and the steel plates in a 

 local spot may become hot enough to fry an egg; so, in the standby 

 condition, temperature will far exceed the 90° F. for water. For 

 its protection, the equipment might have to stand a temperature 

 spread of 28 to 168, or 140° F. On the other hand, what if the same 

 equipment is mounted on the "sail" of a nuclear submarine? You 

 are cruising along under the ice and the temperature is close to 

 freezing, say 28° F. Suddenly, you decide to come up, and, like the 

 Skate, break through the ice. The air temperature may be minus 

 50° F. , so you get an almost immediate drop of 78° F. Now you 

 need to design for protection from minus 50° to plus 168°, a spread 

 of 218° F. Also, effects of the rapid cycling of temperature on the 

 materials used are important. So environmental linnitations must 

 be furnished for equipment design. In addition to the cycling ef- 

 fects and temperature, the factors of wave motion, vibration, 

 radioactivity, corrosion, fouling, shock, and stresses of all kinds 

 are of interest. 



Let me emphasize again that the Bureau of Ships is a user- 

 consumer, relying heavily on the Office of Naval Research, the 

 Hydrographic Office, and the private laboratories for environmen- 

 tal information. With regard to instrumentation in the specific 

 areas sponsored by the Bureau of Ships, the bulk of oceanographic 

 instrumentation development is carried out and funded as a part 

 of the approved programs at our Bureau-managed laboratories. 



The remainder of this paper briefly covers some of the spe- 

 cific areas of interest to the Bureau of Ships and its laboratories. 

 Of particular interest are the following: (1) Acoustic Measurements, 

 (2) Wave Motion, (3) Antifouling and Corrosion Effects, (4) Deep 

 Current Velocities, and (5) Deep Sea Floor Characteristics. 



The Bureau of Ships' interest in ACOUSTIC MEASUREMENTS 

 is understandable both from the point of view of offensive and 

 defensive capabilities of the fleet. Other speakers have mentioned 

 to you direct sound-velocity measurement. A good and partially 

 satisfactory instrument (The National Bureau of Standards Sound- 

 Velocity Meter) has only recently beconne available in small quan- 

 tities. Here is a case where a problem of measuring a property 



140 



