20 
MR. J. W. CAPSTICK ON THE RATIO OF THE SPECIFIC HEATS 
trary units. Dividing these by the pressures, the corresponding volumes are obtained. 
These are given in Table IV., and in fig. 7 they are plotted on a curve, taking as 
ordinate and v as abscissa. The inclination of this curve to the horizontal axis at 
any point gives the value of d {pv) / dv at that point. To get the v corresponding to 
the pressures used in the velocity of sound exj^eriments, it is sufficient to take an 
approximate value of and divide by the pressure. The volumes so obtained are 
given in the second column of Table V., and, dividing the rate of change of at 
these points by the pressures, we get the numbers shown in the third column. 
Fiv. 6. 
1 
ABLE IV. 
Table V, 
V- 
V, 
I cl (pv) 
p dv 
380 
14-9 
•007 
.580 
9-8 
•014 
600 
9-5 
•014 
680 
8-3 
•015 
P- 
pv. 
V. 
382 
57012 
14-93 
602 
56752 
9-43 
533 
56850 
10'65 
660 
56657 
8-58 
We have then, finally, the following table for the ratio of the specific heats, where—• 
