g2 PRELIMINARY ACCOUNT OF AN INQUIRY INTO 
To sum up the above, it appears that the intestines possess an intrinsic 
ganglionic apparatus which is in all cases essential to the peristaltic movements, 
and, while capable of independent action, is hable to be stimulated or checked 
by other parts of the nervous system ; the inhibiting influence being apparently 
due to the energetic operation of the same nerve-fibres which, when working 
more mildly, produce increase of function. 
After the above conclusions had been arrived at, my attention was directed 
by Professor Goodsir to a paper by Dr. O. Spiegelberg, published last year, 
in which he shows that the movement of the intestines is increased by 
mechanical irritation of the cord. His results are particularly satisfactory, as 
having been obtained incidentally during an inquiry into the movements of 
the uterus, and so without any preconceived theory. Spiegelberg also attri- 
butes the increased peristaltic action after death to arrest of the circulation, 
having found that the same thing occurs during life when the aorta or vena cava 
is compressed above the origin of the mesenteric vessels. 
To proceed to the experiments upon the cardiac movements : some of these 
consisted in irritation of the vagus in rabbits, and this was followed by different 
results in different instances: thus, on one occasion the pinching of the cardiac 
end of the left nerve, divided in the neck, was followed by considerable increase 
in the number of beats as felt through the walls of the chest, but similar treat- 
ment of the right nerve afterwards caused great depression of the heart’s action. 
Again, in one animal the evidence obtained from mechanical irritation of the 
vagus was almost entirely negative. In another case, the left vagus having been 
exposed, feeble galvanic currents transmitted through the nerve, isolated by 
a plate of glass placed beneath it, were succeeded by slight increase in the 
number of contractions. The strength of the battery having been then in- 
creased by introducing the rods into the helix, it produced first irregularity, 
and then complete arrest of the action of the heart, which had been previously 
exposed. No sign of recurrence of contraction appearing, I filled the jar to the 
top with acid solution, and sent powerful currents through the vagus, with the 
instantaneous effect of reviving the action of the heart, which, on their immediate 
discontinuance, continued to beat, though feebly, for several minutes. During 
this time I again applied the galvanism very mildly, and the result was great 
increase in the number of beats on several successive trials. The apparent 
discordance of these facts is, I believe, partly owing to differences in the state 
of the nerves in different cases as respects irritability and exhaustion, as will be 
better understood from the sequel ; and, on the whole, the experiments appear 
to show that, in a healthy state of the nervous system, very gentle irritation of 
‘ Henle and Pfeufer’s Zezischrift, 3rd series, vol. il, part 
