They have been produced by artificial inducement of spawning, and 

 we believe that they can be bred selectively for certain desirable 

 characteristics, such as rapid growth and disease resistance. 



Not as much has been done with commercial food fishes, with 

 the possible exceptions of salmon, carp, and catfish. There has 

 been some hybridization. Considerable work has been done in other 

 countries. We are also interested in the possibility of using rice 

 ponds in this country for growing fish, too. This provides mutual 

 benefit. It grows better rice if we have fish in there because they 

 keep the roots clean, and the fishes, such as, carp and buffalo- 

 fish, can grow quite rapidly in rice ponds. 



We are doing something along these lines, but we have a long 

 way to go. 



MR. THEODORE J. SMITH (Packard Bell Computer): Of the 

 20-odd transducer types mentioned for survey vessels, indicate 

 the number which provide output in the following ranges: to 10 

 v.d.c, Otolv.d.c, OtoIOmv.d.c, and 1 mv.d.c. or less. 



MR. B. K. COUPER (BUSHIPS): The range for most transducers 

 or sensors would be, perhaps, - 5 v.d.c. However, the ranges 

 and accuracies desired are usually expressed in other units, or, 

 in some cases, merely indicated in the hope of improvement in 

 present designs. These 20-odd transducers to which you refer 

 have not yet been ordered -- for the most part. You will notice 

 that the handouts (appendices E, F, G, and H) tend to be per- 

 fornnance rather than engineering specifications, and so it is not 

 known what their output will be. 



MR. THEODORE J. SMITH (Packard Bell Computer): Are there 

 any digital output transducers yet? 



DR. W. S. RICHARDSON (WHOI): Yes, there are several pressure 

 transducers, such as the vibratron, which are essentially digital 

 devices, if you include with the sensor the annplifier service sys- 

 tem. Of course, this is the most common type of system in 

 instrumentation. 



MR. SCOTT A. MILLS (Ramo-Wooldridge): What technique 

 makes Omega more effective than Loran, and when will Omega be 

 in worldwide operation? 



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