130 Mr. Dalton on Sulphuric Ether. [Feb. 



Table of the Forces of Aqueous, Alcoholic, and Ethereal Vapours. 



Dr. Ure's numbers for ether corresponding to the above, the 

 last exclusive, are 6-55, 13, 25-7, 49-8 [49], 96-4 ; the ratio is of 

 course less than two, and a descending one ; namely, 1-98, 1-97, 

 1-94, and 1-93; this last circumstance characterizes a mixed 

 liquid- 



I have not extended the experiments on ether further than 

 212° ; but as that temperature gives a force of 207 or 209, 1 esti- 

 mate the force to be 240 at 220° nearly. 



If the forces registered in the preceding table be allowed as 

 near approximations to the truth, it must; 1 think, be admitted 

 that they increase in geometrical progression to the same inter- 

 vals of temperature for a range of 200° at least. Whether those 

 intervals of temperature are equal one to another successively is 

 another inquiry, which the above facts and observations do not 

 enable us to decide. 



Analysis of Ether by Electricity, S)C. 



When a little fluid ether is let up into Volta's eudiometer, 

 either over mercury or water, and a small portion of azotic gas 

 is likewise sent up, in order to be vapourized by the ether ; then 

 if the vapourized air be electrified for an hour, some permanent 

 ^as is produced, and charcoal is precipitated. The gas when 

 washed is chiefly or wholly carburetted hydrogen ; for it takes 

 two volumes of oxygen, and yields one of carbonic acid gas. If 

 the vapourized gas be dry and over mercury, a volume of vapour 

 yields two volumes of carburetted hydrogen, and moisture is 

 perceived within the tube. If the electrification were continued. 



(a) Southern, 4-71. Ure, 4-70 

 (i) Southern, 13-00. Ure, 12-95. 

 (c) Southern, 35-20, Ure, 35-50. 



(rf) Southern, 88-00+ . Ure, 8900. 90. The mean of inj' two tables. 



(e) This ohservatidii is Mr. Southern's. There is reason to suspect his tempera- 

 tures too high for his forces in the high pressures. They exceed Dr. Ure's. 

 if) Ure, 4-02. 

 {g) Ure, 11-20. 

 (A) Ure, 30-00. 

 (i) Ure, 78-50. Bettan, 82. 



