228 



CAPTAIN SABINE ON THE REDUCTION TO A VACUUM 



then pumped out till the gauge indicated 1.4 inch. A fresh supply of gas was 

 then introduced, passing through the cylinder containing fresh muriate of 

 lime, till the pressure withinside the apparatus exceeded by about 0.2 inch the 

 pressure of the atmosphere on the exterior. An equilibrium of pressure was 

 then produced, by permitting the escape of the small portion of gas necessary 

 for that purpose. The mercury in the included barometer stood at 29.95, 

 corresponding to the indication of the standard barometer of 30.24 inches at 

 SSfiJi The following observations were then made. 



The apparatus was then left during the night filled with the gas, and on the 



; next morning a fresh impulse was given to the pendulum, and the observation 

 I 

 repeated. 



Observers. 



Thermometers. 



In. 

 eluded 

 Barom. 



Times of 



Disapp. Re-app. Coincidence. 



Arc registered 

 and true Arc. 



Mean 

 Interval. 



Correc- 

 tion for 

 Arc. 



Reduc- 

 tion to 



Corrected 



Vibrations 



at 36°. 



Mr. 

 Taylor. 



Captain , 

 Sabine. 



1 



2 

 3 

 35 

 36 

 37 

 38 

 39 



38.8 



38.9 



38.8 



39.0 



inch. 



29.'88 

 29.'87 



54 46 

 03 12 

 11 38 

 41 43 

 50 09 

 58 34 

 07 00 

 15 26 



54 58 

 03 24 

 11 50 

 42 07 

 50 37 

 59 07 

 07 36 

 16 06 



m a 

 03 18 



4 58 50.5 



Div. o 



0.86 = 1.03 



0.30 = 0.36 



;>506.64 



+ 0.73 



+ 1.20 



38.85 



29.875; Index + 0.32; Reduction to 32° —0.025; = 30.17. 



86314.24 



86314.24 



The vibrations in this experiment were as follows : 



T 1 1 f February 9 . . 86313.93; Barom. 30.215 inches. 



In hydrogen gas I p^^^^^^^j^ 86314.24; Barom. 30.170 



Mean 

 In atmospheric air, February 9 



86314.085 ; Barom. 30.1925 

 86305.57; Barom. 30.193 inches. 



