469 
1910-11.] Isopiestic Expansibility of Water. 
In this formula sufficient approximations are given by taking 
v = 2-0c.c. a = 2 - 10~ 6 
jgV'j = 1*5 c.c. £ = 440 6 
In our example given above — 
W 
y — 41*10~ 6 . 
13-56 
J— = *205 c.c. 
and 
w - W 
112 = -288 c.c. 
12-56 
Substituting in (1) and (2), and calculating the corrections for various 
values of p, we get the following Table : — 
Pressure 
in 
kgs./cm. 2 
Uncorrected 
Initial Yol. 
Corrected 
Initial Yol. 
U ncorrected 
Change of 
Yol. 
Corrected 
Change of 
Yol. 
Corrected 
Final Yol. 
Ratio. 
Corrected 
Final Yol. 
Corrected 
Initial Yol. 
400 
•288 
■282 
•205 
•211 
•493 
1-75 
* 700 
•288 
•279 
•205 
•215 
•494 
1*77 
£1000 
•288 
•276 
•205 
•219 
•495 
1-80 
Correcting also the temperatures to which these volumes correspond, 
we get — 
Pressure. 
Final Yol. 
Uncorrected 
Temperature T. 
Corrected 
Temperature 
(T - 25). 
Initial Yol. 
400 
1-75 
328° 
303° 
700 
1-77 
369° 
344° 
1000 
1-80 
413° 
388° 
As explained above, the correction is 25° in this case, because here — 
Vol. of bulb = -506 c.c. and final volume of liquid = *494 c.c. 
All the observations were treated as explained above, and the following 
table gives the values of V T and ^ ^ for various values of T, where 
V T represents the volume at temperature T degrees centigrade, and Y 0 is 
roughout as 100 c.c., i.e . — 
initial volume + change in volume 
the initial volume, taken throughout as 100 c.c., i.e . — 
V T = 100 x 
initial volume. 
