THE VELOCITY OF SOUND WAVES IN TUBES. 
ARTHUR L. Fouey, Indiana University. 
(Author’s Publication No. 45.) 
In 1862-63 Regnault, in Paris, made an elaborate series of experi- 
ments on the velocity of sound in newly laid water pipes. As sources 
of sound he used a pistol, explosions, and musical instruments. Both 
ends of the pipe were closed and the sound was produced at one end. 
Thus the wave passed back and forth through the pipe many times, its 
time of arrival at the ends being recorded on a chronograph drum by 
a stylus operated electrically when the sound wave impinged on a thin 
membrane and closed an electric circuit. Figure 1 shows graphically 
the results of Regnault’s experiments. 
Metres 
per Sec. 
Velocities of Sound 
10.000 15,000 20,000 
Distances traversed in the Pipes Metres 
Fig. 1 
