Memoir on Sulphuric Ether: = 477 
residue of gas being examined, is found to 
contain a little carbonic acid, some new 
combustible gas, and oxygen in various pro- 
portions. In short, the operation is very in- 
complete, owing to an excess of ether va- 
pour. 
(b) If the oxygen gas be good, and the 
volume be increased from 100 to 150 by 
the vapour. (which will naturally arise in 
temperatures between 40° and 50°, and ‘in 
higher temperatures the volume may be redu- 
ced by cautious agitation, till the water has 
absorbed part of the superfluous ether and 
vapour), then a spark produces a violent ex- 
plosion, The gaseous volume is doubled, or 
from 150 becomes 300; and upon examina- 
tion is found to consist of carbonic acid and 
new combustible gas, but chiefly the latter. 
Little or no oxygen is found, 
_ If the ether vapour be only from 3 to 10 
per cent. of the volume of oxygen, the ex- 
plosion is vigorous, and a complete combus- 
tion takes place. The residue consists of 
carbonic acid and oxygen gases only. 'Ten 
volumes of ether vapour require about 60 of 
oxygen, and produce about 40 of carbonic 
acid, 2 43 
_(c) If 100 oxygen. be increased by ether 
vapour to 120 or 130, a vjolent explosion en- 
