SI 6 Dr Turner’s Experiments on the Application of 
Dcebereiner imagines that galvanism is the principle concerned ; 
that, by putting platinum into an explosive mixture, we esta- 
blish a simple galvanic circle, in which the hydrogen represents 
the zinc. That ingenious chemist has not, to my knowledge, 
advanced one argument in proof of his assumption, and has 
been led to it purely, as I imagine, by the impossibility of ex- 
plaining phenomena on any other known principle. It is, how- 
ever, better in science to account for phenomena on known 
principles, than to search unnecessarily for new ; and, as galva- 
nism does afford us a rational explanation, while we have .no po- 
sitive proof that it is not the agent concerned, we can hardly 
refuse a certain degree of belief to the ingenious supposition of 
Prof. Dcebereiner. The facts which have been stated in the 
present paper give additional plausibility to this view ; for, on 
taking a comparative survey of the two Tables, which show the 
effect of gases in preventing the action of electricity and plati- 
num, a singular coincidence will be observed, which certainly 
cannot be the result of chance. One or two exceptions do in- 
deed occur, but these are far outweighed by the instances which 
are favourable to this side of the question, and which may be 
adduced in support of it. It must, on the contrary, be confess- 
ed, that all my attempts to render electrical excitement evident, 
by means of an electrometer, have wholly failed. This nega- 
tive argument does not, however, merit much confidence, be- 
cause the copious production of water forms such a conducting 
atmosphere around the metal, as effectually to prevent the most 
delicate electrometer from being affected. 
Before concluding this paper, I shall mention a few detached 
facts, which may not be uninteresting to the Society, and which 
will show what precautions are necessary for ensuring the regu- 
lar action of platinum. 
On exposing pure spongy platinum to the air and dust of an 
ordinary sitting-room, the metal gradually loses its peculiar pro- 
perty. After three days it still became luminous from a jet of 
hydrogen, but at the end of six days no action ensued, not even 
when it was put into a mixture of oxygen and hydrogen. By 
simply igniting the platinum, its energy was completely restored. 
A piece of platinum was kept in a closed drawer of the same 
