332 Mr. D. J. Blaikley on the 



factor \/ - ; and if the influence of n is properly represented 



by a /-, the mean of all the values of V should agree with V 



as obtained from v 1 and v 2 . The mean is 331*676 metres; and 

 the latter value is 331*620, with which the mean is in very 

 close agreement. The pairs of adjacent values v 4 and v B &c. 

 are rather ill-conditioned for the determination of V : the best 

 value of V should be from the extreme values of v — that is, the 

 pair v 4 and v. This value is 331*603 — very little different from 

 the value 331*620 obtained from v 2 and v 1} where there is no 



variation in the value of \ / -. From these results it would 

 V n 



appear that the influence of the vibrational rate of stationary 



waves in tubes upon the velocity is properly represented by 



a / - ; but as Lord Rayleigh, in the paragraph quoted, refers 



to Schneebeli's and A. Seebeck's investigations, based upon 

 Kundt's experiments, we may calculate a value for V upon 

 their determinations. According to these observers, when n 

 varies, the diminution of velocity is proportional rather to 



a / -g than to \ /-• Taking the pair of velocities v and v 4 , 



and substituting \/ — 6 for a /-, we get V = 334*439 — mani- 

 festly too high, and very different from 331*620, the value 

 obtained from the pair v x and v 2 . 



In the diagram (Plate VII.) and in Table VIII. I have 



therefore used i/ - ; but this, or any modification of it such 

 as a/ — , can only be applicable, and then but approximately, 

 within certain limits. 



Table VII. 









Table VIII. 









Calculated velo- 

 city, in metres, 

 at the pitch of 

 260 vibrations. 



Comparison between values of v, v v v 2 , v 3 , v 4 , as observed 

 and as calculated, at the pitch of observation s, V being 

 taken as 331 -676 metres. 



Eadius. 



Velocity, in metres. 



Differences. 



n, or 

 pitch. 





Observed. 



Calculated. 



- 



+ 



323-728 

 326-884 

 328-792 

 329-943 

 330-635 



r 



•005715 

 •009524 

 •015874 

 •026457 

 044095 



V 



V 2 



324-383 

 326-902 

 328-784 

 329-723 

 330134 



324-514 

 326-884 

 328-792 

 329-545 

 330-209 



•018 



•178 



... 



•131 



•008 

 •075 



322-96 

 260-36 

 26018 

 172-48 

 13115 



