124 



Mr. Dalton on Sulphuric Ether. [Feb. 



of ether = 37'5 gr. and this quantity 



Now 49*5 measures 

 "being by the manometer = J-J-f of the atmospheric pressure, we 

 have 113 : 37-5 :: 772 : 256 gr. the weight of 253 cubic inches 

 of ethereal vapour of atmospheric force ; but the vv'eight of the 

 same volume of common air = 77 gr. Hence ethereal vapour 

 = 3*3 times the specific gravity of air. 



I find amongst my notes in 1805 a similar experiment, from 

 -which the specific gravity was deduced = 2-65 only. This 

 difference occasioned me to repeat the experiment as follows : 



Balloon co7itaining 404 Cubic Inches = 123 Gr.of Air. 



Barometer, 30 inches. 



Ether, 0*728 specific gravity in the temperature 48". 



1819— Feb. 25 



26 



27 



10 

 1 



3 



6^ 

 7 

 9 

 9 



114 

 2 

 6 

 9 

 9 

 9 



a. m. 

 p.m. 



a. m. 



, m. 



a.m. 

 p.m. 



At this period the cock was turned, and the air and vapour let 

 out, till the equilibrium was restored with the atmosphere, the 

 barometer being then 29"5 ; the thermometer was not noted. In 

 a few minutes the cock was again turned, and the experiment 

 continued. 



Manometer. 



. . 4077 . 



. . 4040 . 



.. 4025 . 



.. 4006 . 



.. 3985 . 



.. 3969 . 



. . 3950 . 



.. 3937 . 



.. 3919 . 



.. 3908 . 



.. 3890 . 



Measures of ether 

 evaporated. 



. .. 0-0 

 . . . 5-5 

 . .. 7-5 

 . .. 10-0 

 . .. 14-0 

 ... 15-5 

 ... 18-0- 

 ... 19-5 

 . .. 22-0 

 ... 24-0 

 ... 25-0 



