35 
not, therefore, seem dependent upon the quantity of oxygen 
in the water, but principally upon the caloric therein, which 
may enable the hydrogen to assume a gaseous form. 
These and other similar facts, contrasted with the very 
different phenomena attending the action of free or atmos- 
pheric oxygen, led us to suspect some essential difference 
between the free oxygen of the air, and that combined in 
water or vapour : the first being absolutely requisite to com- 
bustion, and the latter appearing incapable of maintaining 
that process. 
We could not, however, draw this conclusion, because it 
was opposed by some experiments in electricity and galva- 
nism : for when water is subjected to the action of an electric 
or galvanic discharge, by means of golden or platina wires, 
its two constituent gases of oxygen and hydrogen are pro- 
duced, and these identical gases, found capable of reduction 
again into water, by being fired together. Hence it appears 
that oxygen may be obtained from water, fit for the support of 
combustion. The difficulty stated as arising in this experi- 
ment is quite satisfactorily explained in the following. 
During the embarrassment hereby occasioned, and after we 
had made the preceding remarks, we met with Dr, Pearson's 
Experiments in Electricity, where we find him asserting as 
the result of a great number of experiments : — " It is 
" demonstrable that the electric discharge and spark contain 
" fire, and very probably they are merely a state of fire, &c." 
"It is demonstrable, also, that the ponderable parts of 
" oxygen and hydrogen constitute water. There is strong 
" evidence that these gases consist of a peculiar species of 
" matter, which is ponderable, and of imponderable matter, 
" which is that which is separable from them in the state of fire 
" or flame." It has been rendered at least very probable, 
" that when water or its constituent gases, oxygen and hydro- 
" gen, are rendered into the gas state, they absorb or unite 
" with a large quantity of caloric, or of both caloric and light." 
D 2 
