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THE ROYAL SOCIETY OF CANADA 



does not change at these high frequencies within the limits of experi- 

 mental error. More than one reading was taken for each length of bar, 

 but space does not permit the publication of all of these values, 

 as the observations did not differ by more than one millimeter in 

 total distance measured. 



Table I. 



Table II. 



The curve, figure 2, which gives the relation between the wave- 

 length in the metal (twice the length of the bar) and the wave-length 

 in the tube, shows that this relation is strictly linear. This means 

 really that the ratio of the velocities of these longitudinal elastic 

 vibrations in metal and in air remains constant through the range 

 of these high frequencies; if one changes, the other changes in the 

 same ratio. Since it is highly improbable that the velocity in air 

 changes at all, we may take it as a result that the velocities in metals 



