of charcoal and hydrogen. 157 
results of the combustion of a quantity of gas, which he had 
himself prepared from oil. One volume was found to con- 
sume three volumes of oxygen, and to yield little short of 
two volumes of carbonic acid, in those respects agreeing 
nearly with olefiant gas ; but when mingled with more 
than the requisite proportion of chlorine, it was not, as ole- 
fiant gas would have been, entirely condensed, but suffered 
a diminution of only four tenths of its bulk, the remaining 
six tenths, after being freed from the redundant chlorine, 
agreeing in its properties with carburetted hydrogen. For 
example, 10 volumes of this gas (containing four of gas 
condensible by chlorine and six of carburetted hydrogen) 
consumed 30 volumes of oxygen, and gave 18 of carbonic 
acid. But of the oxygen, 12 volumes are due to the six of 
carburetted hydrogen, leaving 18 volumes for the combustion 
of the four volumes of gas condensible by chlorine, which 
is in the proportion of to 1. Of the 18 volumes of car- # 
bonic acid, also, six may be traced to the combustion of 
the carburetted hydrogen, leaving 12 volumes as the product 
of four of the condensible gas, or in the proportion of 3 to 1. 
The portion of gas, condensed by the action of chlorine pre- 
sents, therefore, decided differences from olefiant gas, in 
requiring not three only, but 4^ volumes of oxygen for 
combustion, and in affording 3, instead of 2 volumes of car- 
bonic acid. Nearly the same relation of the oxygen con- 
sumed, and carbonic acid produced, to that part of the gases 
from coal and oil which is condensible by chlorine, existed 
also not only in other experiments of Mr. Dalton, but in 
all those which I have myself made. The proportions I have 
found to vary in different cases from to 5 volumes of 
