224 



CAPTAIN SABINE ON THE REDUCTION TO A VACUUM 



The vibrations in air in this experiment were as follows : 



January 17. Previous to the vibration in") o/'on^ lo t> «« z^^^rv • i, 



the rarefied medium j 86304.13 ; Barom. 29.670 mches. 



January 18. Subsequent to the vibration! o/-ono i^a -o «« »to*, 



in tl/e rarefied medium | 86303.94 ; Barom. 29787 



86304.03 ; Barom. 29-728 



The vibrations in a rarefied medium, re-1 o^oio c^n r^ o r/^ • i. 



duced to the same temp, as those in air j ^^^^^'^^^ ^^^^^ ^ i'^^^^^' 



Whence the result, that a difference of 9. 17 vibrations per diem corresponds to a 

 difference of atmospheric pressure of 26.138 inches of mercury at 32°: the tempe- 

 rature of the air of full pressure being 32°.37, and that of the rarefied air 32°.45. 



Exp. V. — Januaiy 30th and 31st. Clock gaining 4" 14^38. In air. 



The air was then withdrawn, and the following observations made. The air- 

 pump had been repaired, but 0.6 inch was the limit to which exhaustion could 

 be carried by its means. The leakage of the apparatus did not exceed seven 

 hundredths of an inch in the 18 hours of the experiments. 



