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Abstract of Communication, ‘‘On the VARIATIONS 
PRODUCED in the ELECTRICAL CONDITION of 
the VISCERA by STIMULATION of ADJACENT 
CUTANEOUS NERVES.” 
By R. Caton, M.D., F.R.C.P., 
PROFESSOR OF PHYSIOLOGY IN UNIVERSITY COLLEGE, LIVERPOOL. 
[ Read 11th January, 1889.] 
In studying the electric phenomena of nerve and muscle, 
it is well known that a change in the electrical state—the 
negative variation or current of action—occurs during 
frictional activity, and that in all nerves other than motor 
and secretory ones it forms the only objective phenomenon 
by which the transit of a nerve impulse can be recognised. 
Haying a definite object in view relating to practical 
medicine, I was wishful to ascertain whether stimulation 
of the cutaneous nerves of the trunk had any influence 
on the nerves of the internal organs. 
The only mode of ascertaining this was to find out ifa 
negative variation in the electrical condition of these nerves 
or of the organ to which they are distributed occurs at the 
instant when the stimulation of the cutaneous surface takes 
place. The following experiment was therefore performed, 
and frequently repeated. A frog was rapidly and painlessly 
killed by destroying its brain; a small quantity of woorain 
was then injected into a lymph sac, to prevent reflex 
spasm ; a small coil of intestine was withdrawn through 
an opening in the left flank, and two non-polarisable 
electrodes were so arranged as to bring this coil of intestine 
into the circuit of a sensitive galvanometer. The needle 
at once showed a certain amount of deflection. This being 
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