[lang] high frequency VIBRATIONS, ETC. 173 



The distance d of these regions of maximum and minimum 

 disturbance from the disc is given approximately by 



where the constant K is defined by the relation R = k\, R and X 

 being defined as above, and n has all integral values commencing at 

 unity. 



The odd values of n dfetermine the distances to the successive 

 maxima, and the even values of n to the successive minima, com- 

 mencing with the farthest from the dis::. Thus the farthest point 

 of minimum disturbance (n = 2) is found to be at a distance of 3.1 

 cms. from the end of the bar 5 cms. in length and 2.54 in diameter. 



Both of these effects just discussed must be kept in mind in using 

 this method for the study of high frequency vibrations, but they 

 need not affect the results of such measurements as are given here 

 if the loops are measured a short distance away from the end of the 

 tube. 



The experiments here described have been found very suitable 

 as a laboratory experiment for students, and are now used in this 

 laboratory. 



In conclusion, my thanks are due to Prof. Boyle, who suggested 

 this research and kindly followed its progress. 



Physical Laboratory, 

 University of Alberta. 



