252 DR. LOUIS YESSOT KING ON THE PROPAGATION OF SOUND IN THE FREE 
of readings at this position are given to demonstrate the remarkable uniformity of intensity of the 
successive blasts. The results are shown graphically in fig. (ii.). 
Fig. (ii.). Resonance curve of Webster phonometer with reference to sound-waves generated by the 
diaphone. 
Table II. 
Resonator 
position. 
No. of 
observa¬ 
tions. 
Mean 
phonometer 
observa¬ 
tions. 
Resonator 
position. 
No. of 
observa¬ 
tions. 
Mean 
phonometer 
observa¬ 
tions. 
Resonator 
position. 
No. of 
observa¬ 
tions. 
Mean 
phonometer 
observa¬ 
tions. 
o-o 
1 
0-9 
6-9 
1 
3-8 
8-4 
2 
6-0 
1-0 
1 
0-9 
7-0 
5 
4-3 
8-5 
3 
5-6 
2-0 
1 
1-0 
7-1 
1 
4-3 
8-8 
9 
5-6 
3-0 
2 
1-05 
7-2 
1 
4-6 
9-0 
3 
5-0 
4-0 
3 
1-3 
7'4 
3 
5-2 
9-2 
1 
4-4 
5-0 
4 
1 -55 
7-5 
4 
5-4 
9-4 
1 
4-2 
6-0 
4 
2-7 
7-6 
1 
5-9 
9-6 
1 
3-7 
6-5 
1 
3-2 
7-8 
2 
5-8 
10-0 
3 
3-1 
6-6 
1 
3-2 
8-0 
26 
5-5 
6 * 8 
1 
3-6 
8-2 
2 
5-9 
Successive readings of i 
r 5-4 
5-3 
5-2 
5-4 
6-3 
6-2 
5*7 
phonometer with J 
5-4 
5-5 
5-5 
5-4 
5-2 
6-2 
5-5 
resonator at posi- | 
5-6 
5-7 
5-7 
5-5 
5-2 
5-3 
tion 8‘0 
L 5-5 
5-6 
5-5 
5-4 
5'0 
5-1 
Air Pressures Opei’ating Diaphone. 
Beginning of Test. 
104 ’5 cm. mercury, falling to 96‘5 cm. at end 
of blast. 
Mean pressure between blasts, 19 - 4 lbs./sq. in. 
above atmospheric. 
End of Test. 
106 - 5 cm. mercury, falling to 98'5 cm. at end 
of blast. 
Mean pressure between blasts, 19 • 7 lbs./sq. in. 
above atmospheric. 
According to theory resonance curves obtained in this way for the same frequency, but for signals of 
different intensities should have their ordinates proportional. It would seem at first sight that for very 
intense waves the sensitivity of the phonometer could be reduced in the ratio of 6 to 1 by taking readings 
