On Chemical Philosophy. M5 
capacity; but I have also already hinted, that I conceive the 
methods hitherto used to ascertain capacity to be fallacious, 
and of course that the tables in some instances are erroneous 3 
that it is not alone the transference of heat from one body to 
another, or the quantity of ice which bodies will melt in cooling, 
which can determine it; but how far this power is separated in 
its pure and unconfinable form, and of course makes its escape 
without having time to produce any of these effects. —But of this 
more afterwards. 
This explanation of galvanism will beautifully apply to the 
evolution of gas in coal pits. It is confirmed by the fact lately 
ascertained,—that a heated atmosphere increases the power of 
galvanism. It is confirmed too by a review of those circumstances 
which modify the actions of this power in galvanism, and render 
them so different in their effects and appearances to those which 
it produces in the form of electricity. Let us then examine these 
differences. Every fact connected with the discovery of- gal- 
vanism, and the history of its progress, proves the explanation I 
have given to be the true one. They prove that positive and 
negative are mere relative states of existence, produced by that 
arrangement of conductors and of substances which, by the 
changes they induce, calls forth a current or stream of this 
power; which depends on the same principles, though varied by 
circumstances, as that which is produced in the form of elec- 
tricity. 
Gatvanism I shall therefore define “ as that object of science 
which treats of some of the CHEMICAL AND NATURAL means of 
PARTIALLY separating the GRAND AGENT from some of ils come 
binations, and of ascertaining its actions tn this state.” 
Electricity I have considered as the most pure and separate 
form of fire, or of the power which produces the phenomena of 
heat and flame; and consequently more attenuated than any 
other, more rapid in its movements, and less resistible in its 
passage through substances. Galvanism' I consider to be the 
same power, only partially separated from its combinations, and 
differing widely in all these respects. Hence we perceive the 
solution of that most interesting question, stated, but not an- 
swered, in that valuable work the Edinburgh Encyclopedia, 
“ How do Galvanism and Electricity differ from each other?” 
If we attend to the solvent, attractive and energetic properties 
of this power, as already pointed out, and the different methods 
peculiar to its production in electricity and galvanism, it is evi- 
dent that they must differ from each other. In electricity we con~ 
trive by mechanical means to collect the loose and “ uncom- 
bined quantity” from the earth and surrounding medium: and 
this we do in circumstances in which it has nothing to act upon, 
H2 as 
