16 
SIR HUMPHRY DAVY’S ACCOUNT OF 
Mola di Gaeta, with an apparatus in which the smallest possible surface of 
silver was exposed, and in which good conductors, such as solutions of potassa 
and sulphuric acid, were made to connect the circuit ; but with the same 
negative results. 
Having obtained a larger Torpedo at Rimini in June in the same year, I re- 
peated the experiments, using all the precautions I could imagine, with like 
results; and at the same time I passed the shock through a very small circuit, 
which was completed by a quarter of an inch of extremely fine silver wire, 
drawn by the late Mr. Cavendish for using in a micrometer, and which was 
less than the ToVodth of an inch in diameter ; but no ignition of the wire took 
place. It appeared to me after these experiments, that the comparison of the 
organ of the Torpedo to an electrical battery weakly charged, and of which 
the charged surfaces were imperfect conductors, such as water, was more cor- 
rect than that of the comparison to the pile : but on mentioning my researches 
to Signor Volta, with whom I passed some time at Milan that summer, he 
showed me another form of his instrument, which appeared to him to fulfill the 
conditions of the organs of the torpedo ; a pile, of which the fluid substance 
was a very imperfect conductor, such as honey or a strong saccharine extract, 
which required a certain time to become charged, and which did not decom- 
pose water, though when charged it communicated weak shocks. 
The discovery of CErsted of the effects of Voltaic electricity on the magnetic 
needle, made me desirous to ascertain if the electricity of living animals pos- 
sessed this power ; and after several vain attempts to procure living torpedos 
sufficiently strong and vigorous to give powerful shocks, I succeeded in Oc- 
tober of this year, through the kind assistance of George During, Esq., His 
Majesty’s Consul at Trieste, in obtaining two lively and recently caught Tor- 
pedos, one a foot long, the other smaller. I passed the shocks from the largest 
of these animals a number of times through the circuit of an extremely delicate 
magnetic electrometer, (of the same kind, but more sensible, than that I have 
described in my last paper on the electro-chemical phsenomena, which the 
Royal Society has honoured with a place in their Transactions for 1826 ,) but 
without perceiving the slightest deviation of or effect on the needle; and I con- 
vinced myself that the circuit was perfect, by making my body several times a 
part of it, holding the silver spoon, by which the shock was taken, in one hand, 
