588 MR EDMUND J. MILLS’S RESEARCHES IN THERMOMETRY. 
two with decreasing pressure ; the ninth comparison is derived from two 
observations, the tenth from one observation. 
Pressure in Atmospheres. 
= = A = = Therm. 455. 
Observed. Calculated. 
49:4 49°58 5:25 
58:7 58°74 6°22 
68:71 68:10 Tai. 
776 7744 8:20 
87:0 86°79 9:19 
96°3 96:14 10:18 
105°5 105°58 11:18 
1143 114:27 12:10 
124-0 124:28 13:16 
133°6 ipo io 14:16 
Probable error of a single comparison, ‘11. 
The equation 
Pressure = Degrees x 9°444, 
on which the above calculation is founded, is derived from all the above 
experiments, each experiment being “ weighted” with the number of observa- 
tions it included. It is clear, then, that up to about 134 atmospheres the 
ascent of the mercury in a thermometer’s bulb is proportional to the pressure 
applied, and does not at the higher limit show any indication of a change 
of law. 
