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COMMERCIAL FISHERIES REVIEW 



Vol. 28, No. 7 



A new sonar to track tuna schools in the central Pacific Ocean has been installed aboard the research vessel Townsend Cromwell of the 

 Bureau of Commercial Fisheries Biological Laboratory, Honolulu. Top, workmen cut hole in bottom of ship to allow installation of 

 a retractable shaft which carries the transducers. Bottom left, transducer shaft is lowered into place. Bottom right, engineer stands 

 at console explaining working of sonar to technicians who will use it. 



