OF THE NATIONAL RESEARCH COUNCIL 119 



friction in the bearings prevents any accidental lag. A noise 

 roughly approximating the revolution of a submarine propeller is 

 produced by rubbing the tube lightly with a bare lead-pencil lead. 

 If a circular motion is given to the lead the number of revolutions 

 as well as the noise quality can be imitated. 



11. The candidate after reading his instructions sits at a table 

 opposite the operator with the simplified compensator between 

 them while the operator rubs the rubber tube at some arbitrary 

 height above the table with the naked lead of a lead pencil. The 

 candidate rotates his compensator wheel until the sound seems to 

 be dead ahead. If the localization is perfect the center of the tube 

 should be directly under the operator's pencil. 



12. Preliminary trials must always be insisted on until the exam- 

 inee has a clear idea of his task. If there is any indication of fail- 

 ure to understand the task the candidate is verbally instructed by 

 the operator. But if inability to understand the task, inability to 

 learn the direction in which the wheel must be rotated, or if gross 

 faults of manipulation are persistent, the candidate is eliminated. 

 The practice is to permit any failing candidate to repeat his exam- 

 ination at any later examination period as long as he is still eager 

 to do so. Eagerness is a good indication. Unfortunately only 

 about one candidate in twenty is able to better his record mate- 

 rially. 



13. If a candidate locates the center within an average error of 

 one cm., quickly, consistently, and without gross variations, he is 

 passed by the examiner. If there is any persistent difficulty a 

 static localization test is given, in which the following points are 

 noted in four grades of excellence: 



{a) Right or left displacement of the center. 

 {b) Breadth of the center, 

 (c) Consistency of the reactions. 

 {d) Quickness and sureness of reaction. 



If the candidate passes this test he is then given another active 

 compensation test. 



14. A strict watch is kept by the operator for disqualifying per- 

 sonal qualities. No grouches, boneheads, discontented or notably 

 immature candidates are knowingly sent on to the School. 



"The success of this selective process has a rather inter- 

 esting theoretical bearing. The task obviously lay outside 

 my proper field, as I do not pretend to know the psychology 

 of audition. Perhaps this was not a serious handicap since 



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