ON THE MEASUREMENT OF TEMPERATURE. 
145 
9. Calculation of the Results. 
The results were calculated by means of the formula : 
V + Y, 
° 1 273-03 
+ YY 
Y 
tls 
2U 
+ T 
ils 
= P 
fY(l - a (273 - T)) 
1 ^ 
+ 
r / o 
+ T 
+ 
Y, 
(Is 
Uo 
+ T',,. 
Where Pq is the pressure on the gas when the bulb and stem \^-ere immersed 
in ice, 
P is the pressure on the gas when the bulb is at tlie temperature to l:)e measured, 
V is the volume of the bullj at 0° C., 
Vj is the volume of the stem from B to C, 
Yifs is the volume of the dead-space, 
a is the coefficient of expansion of the glass, 
273’03 is the melting-point of ice on the gas scale, the reciprocal of the pressure 
coefficient of the gas witli which the thermometer is filled, 
T is the temperature to he measured, 
Ihf and T'js are the temperatures of the dead-sj^ace in degrees Centigrade, 
Tj is the temperature of the stem calcidated from the readings of the auxiliary 
thermometer. 
In calculating T^, the following formula was enqjloved ; 
. 9-0 + 
- I O 
V 
(Is 
273 + T,!s 
= P j- -1-^ 
J .? - i o 
,o -f T 
ds 
Since for each series of observations the ice-point remained constant, the left-hand 
side of each equation could be expressed liy a constant for each filling of the 
thermometer. 
10. Va^oour Pressures of Lieiukl Oxyejen on the Constant-Volume Hydrogen 
Scale. 
(1.) March, 1901. Thermometer A (12 cub. centims. bulb). 
Ice-Point of Thermometer. 
Pressure on gas 
Temperature of dead- 
Constant. 
(corr.). 
space. 
milliin-s. 
°C. 
844•65 
15-30 
38-7114 
VOL. cc.—A. u 
