﻿258 Dr. J. W. Low on the Velocity of Sound in 



of the water in the bottle stood higher than the surface of 

 that in the tube. In this way it was impossible for the air to 

 penetrate into the tube, even though the apparatus had not 

 been air-tight. Everything was, however, always perfectly 

 air-tight. When the tube was full, the stopper at and the 

 clamp on the ear-tubing were removed, the tuning-fork bowed, 

 and the positions of the maxima ascertained exactly as in the 

 case of air. While the observations were being made, the 

 gas apparatus remained in action, so that a slow steady stream 

 of pure carbonic acid poured through the upper portion of 

 the tube and overflowed its edges. 



The observed half wave-length was corrected to 0° C. and 

 760 millim. in dry gas by means of a formula analogous to 

 the one used for air. 



Table showing the observed mean velocities in C0 2 . 



Internal 

 diameter 



c r 



<V 



9,- 



c n . 



c ,ir 



of the 

 tube. 



»=256. 



»=320. 



rc=384. 



»=512. 



n = 1023-25. 



millim. 



28 



metre. 

 255-38 



metre. 

 255-73 



metre. 

 255-86 



metre. 

 25605 



metre. 

 25637 



171 



254-53 



254-96 



25524 



255-36 



255-78 



935 



252-58 



253-03 



253-41 



253-69 



254-49 



By combining the results in the vertical columns in pairs 

 as explained on page 254 for air, we find the following values 

 for the velocity of sound in carbonic acid in unlimited space. 



Tuning-fork. 



Tubes 

 I. and II. 



Tubes 

 I. and III. 



Tubes 

 II. and III. 



Mean. 



c, 



e t ... 



millim. 

 256-7 



256-8 



256-8 



2570 



257-0 



millim. 

 256-7 



257-1 



257-2 



257-2 



257-2 



millim. 

 256-7 



2572 



257-5 

 257-2 

 2572 



Mean 



millira. 

 2567 



25703 



257-17 



257-13 



257-13 





c n 



25703 



For the purpose of comparing my results for air and car- 

 bonic acid with those of other observers, I have constructed 



