132 Mr. Dalton on Sulphuric Ether. [Feb. 



greater or less proportion of vapour, as is the case with oxygen 



gas. 



In respect to the new combustible gas in the above paragraph, 

 its nature may be ascertained by abstracting the carbonic acid in 

 the usual way, and then exploding it with oxygen. In the para- 

 graph (a), the new gas is often nearly pure carburetted hydrogen; 

 but in (t) and (d) it is always a mixture of carbonic oxide and 

 hydrogen in nearly equal volumes; as is proved from its requir- 

 ing 50 per cent, of oxygen, and producing 50 per cent, of 

 carbonic acid. In (b) it is chiefly these two gases, but has a 

 httle carburetted hydrogen occasionally mixed with them. 



When a certain volume of ether vapour is completely burned 

 at one operation, or it is partially burned at the first, as in («), (6), 

 (f), and {d), and the combustion finished by a second operation, 

 still the same volume of vapour requires the same volume of 

 oxygen for its complete combustion, and ]>roduces the same 

 volume of carbonic acid. And it is always found that the car- 

 bonic acid contains two-thirds of the oxygen spent, and conse- 

 quently the hydrogen engages one-third of the oxygen to form 

 ' water. Hence it appears that the combustible element of ether 

 is defiant gas; but as there is reason to conclude that oxygen 

 is one of the elements of ether, it must be combined with 

 hydrogen; so that water must be the incombustible element. 



In order to find what number of atoms of water and defiant 

 gas must be combined to form one of ether, we must have regard 

 to the weights of the different elements which combine. Wow, 

 from the experiments above related, it appears that one measure 

 of ether vapour (weighing 3" 1) requires six measures of oxygen 

 gas (weighmg 6*6) ; but two atoms of olefiant gas weigh 12-8, 

 and one of water weighs 8, making together 20*8, Vv'hich would 

 require six atoms of oxygen, weighing 42, for their combustion ; 

 that is, such compound atom would require rather more than 

 double its weight of oxygen, which is the proportion I find by 

 experiment for ether vapour. Hence then we may conclude, 

 that the atom of ether weighs 20*8, and is compounded of one 

 atom of water and two of olefiant gas. 



In January, 1809, I made an experiment on the slow combus- 

 tion of ether in a lamp, in a large balloon glass. The capacity 

 of the balloon was two cubic feet ; hence the oxygen of the 

 common air in it would weigh 250 gr. nearly. A small lamp 

 with ether was lighted, and instantly dropped into the balloon, 

 which was immediately closed. The lamp burned till it was 

 extinguished for want of air. After a few minutes it was taken 

 out, and the loss of weight ascertained to be 31 gr. The resi- 

 duary gas being examined was found to contain 16 per cent, 

 oxygen, and 3 or 4 carbonic acid ; but in order to obtain the 

 carbonic acid more accurately, the whole volume of air was 

 subjected to lime water, in such manner that all the air which 

 came out was agitated in the lime water that entered the balloon. 

 The quantity of hme water requisite to saturate the carbonic 



