fundamental frequency made it difficult to keep the wave analyzer lined 

 up on any harmonic long enough to get accurate readings. These levels 

 were very much dependent on the standing wave pattern in the pondo 



The optimism of those who hoped to find something that would "work" 

 in g^uiding fish was never greater than on the day of the first trial of 

 the equipment. The U. S, Navy fire department provided a fire truck to 

 pump a sufficient stream of water to operate the wampus in a concrete 

 torpedo testing tank. The noise produced in the result of the einission 

 of interrupted Jets of "slugs" of water and air being expelled from the 

 sound head into the surrounding water as shown in Figure 21. The general 

 effect at close range is rather awesome. The noise escaping from the 

 surface might be compared to that produced by a medium size air cooled 

 airplane engine and propeller running full speed at an equal distance away„ 

 The sound waves set up in the water of the torpedo tank were sufficiently 

 strong to vibrate the s'orrounding concrete under foot. The observers 

 felt peciiliar prickling sensations of the skin and hair follicles when 

 hands were placed in the water approximately six feet from the sound 

 sourcco A slight nausea was experienced by a few. 



For the first exploratory tests at Leetown, 1,000 rainbow trout 

 10 to 12 inches in total length were placed in the counting structure, 

 100 fish to a section^, as in previous tests. The wampus was run out 

 on the trolley to a position 100 feet from the fish in the counting 

 structure, and 1.5 feet below the surface of the pond. The exploratory 

 test of 10 minutes d\iration brought no observable reaction from the 

 trout. Their distribution within the structure remained approximately 

 the same. The level of sound intensity at 100 feet was measured and 

 determined to be U microvolts or 12 db above 1 dyne/cm^. Several hun- 

 dred 2-inch brown trout fingerlings in a live box were unaffected or 

 indifferent. 



Having determined that the trout showed no reaction to the wampus 

 at a distance of 100 feet, the head was moved to a point 30 feet from 

 the fish in the first section. IVhen the sound at that distance proved 

 ineffective, the wampus was placed in its final position for the system- 

 atic trials^ approximately 8 feet from the fish, and 1.5 feet beloi; the 

 surface. At no time, however, did the wampus noise drive the trout 

 entirely from section no, 1 in a manner convincing enough to describe 

 as a scare, Diagramatic results of the tests with this equipment are 

 shown in Figures 23='27. 



For two exploratory trials the wampus was taken to a midpoint in 

 the counting structure and suspended in section no. It. Operating at 

 full power or capacity (water l50 pounds pressure, air 100 pounds 

 pressure) 5 the combination of visual, audible and mechanical stimuli 

 served to drive the trout from sections h and 5 into sections 3 and 6 

 (determined by count). All the trout in sections 3 and 2 as well as 

 those in 6 and 7 turned to head into the current from the sound head. 



25 



