276 
DR. DAVY’S ACCOUNT OF SOME EXPERIMENTS 
show a complicated adaptation of parts, nerves of unusual magnitude rami- 
fying between apparently insensible columns, saturated with a bad conducting 
fluid ; muscles surrounding these columns and fitted to compress them ; and 
a system of mucous glands and tubes adjoining, well adapted to be the medium 
of electrical communication between the two organs and their opposite sides. 
When we consider this structure, it is an easy matter to trace rude analogies 
between it and the pile of Volta, — or between its columns and a battery of 
Leyden jars, such a battery as was formed by Mr. Cavendish for imitating the 
electricity of the torpedo, composed of a large number of jars of very thin glass, 
feebly charged. But these analogies seem to help very little, if at all, towards 
the solution of the great difficulty ; the question remains unanswered, What is 
the cause or source of the electricity ? Here analogy fails entirely ; none of 
the ordinary modes of excitement appear to be at all concerned ; neither fric- 
tion, nor chemical action, nor change of temperature, nor change of form. Let 
us consider for a moment a small torpedo in an active state. The smallest 
which I have employed in my experiments weighed only 410 grains, and con- 
tained only 48 grains of solid matter ; its electrical organs weighed only 150 
grains, and contained only 14 grains of solid matter, — for to this they were re- 
duced by thorough drying. Yet this small mass of matter gave sharp shocks, 
converted needles into magnets, affected distinctly the multiplier, and acted as 
a chemical agent, effecting the decomposition of water, &c. A priori, how in- 
conceivable that these effects could be so produced ! This fish was about ten 
days in my possession, during the whole of which time it ate nothing, and its 
bulk was hardly sensibly altered ; and every day it exercised its electrical 
powers, and to the last they appeared almost as energetic as when it was fresh 
from the sea. This adds, if possible, to the difficulty of explanation. That this 
mysterious function is intimately connected with the nerves, and in a manner 
more striking than all ordinary secretions, is manifest. Beyond this conclusion 
all is darkness ; we have not, as we have in the doctrine of animal heat, ad- 
vanced another step ; we have not been able to connect it with changes in the 
electrical organs as analogous to known sources of electricity, as the changes 
which take place in the lungs in respiration are to the known sources of heat 
or combustion. The attainment of this step is a great desideratum ; and be- 
yond it, probably, we shall never be able to proceed. 
