Figure 6. — View of the main experimental teink from the enclosed platform. 

 Visible at the end of the tank, just ahead of the sump, are stop-log 

 guides, stop-logs in place, and a picket gate beside the standing 

 figure. On the deck above the sump (left center) are three racks of 

 electronic controls. On the rear wall (right center) are control 

 switches for the various pieces of electrical equipment. 



Figure 7. — An experimental tank with electrodes installed for studies of 

 behavior of fish in an electrical field. Black curtains, as shown 

 here, are used around many tanks to prevent visual disturbainces while 

 tests are in progress. Electronic pulse-control units in background. 



