THE GREAT SPINAL ORGANIC NERVE. 
63 
The cardiac plexus that has been just described has been cut 
through, and the heart has at once ceased to beat — the animal 
has died before the complete section of the plexus could be 
accomplished. This would seem to designate the cardiac plexus 
as the source of motor power in this great viscus ; but this con- 
clusion would be erroneous. I destroy an animal — I take out its 
heart as quickly as I can — I cut through it transversely, and I 
perceive the alternate contraction and dilatation of both the 
auricles and ventricles for a certain time. I take the heart of 
another animal that has just been killed, and, while it is yet beat- 
ing, I place it in warm water, and the pulsations are quickened, 
and continue during some minutes, gradually becoming weaker 
and slower, and at length ceasing, but still renewable for a time 
on the application of warmer water. In dividing the cardiac 
plexus I had given a shock to the whole system, which destroyed 
life at once. A blow in the neighbourhood of the great solar 
plexus would produce the same effect. Then what influence does 
the great spinal organic nerve exert, or what influence do other 
nerves exert on the heart? Much, and of a very important 
nature. The great spinal nerve gives intelligence of every 
change that is taking place with regard to the organic move- 
ments, and the organic sensibility, of many of the most import- 
ant viscera : the ganglionic nerve tells of the healthy or morbid 
state of the secretory or nutritive or absorbent system ; and by 
means of the spino-cerebral nerves, the pulse is filled and 
strengthened by hope and joy — it is depressed and rendered tre- 
mulous by sorrow or despair, and the heart responds to every 
emotion of the mind. What an interesting and fruitful field of 
pathological investigation is opened here : but we must not enter 
upon it until the relations of the ganglionic nerve have been duly 
considered. 
ON SPAVINS AND SPLENTS. 
By Nimrod. 
I have been amused with the conflicting evidence of the 
“ Profession,” in the case of Mr. Elmore’s horse ; almost as 
amusing as the twelve certificates of their brethren in Paris, re- 
specting the broken-winded mare, in your number of February 
last. If worth having, the following is my own experience of 
spavins and splents : — 
First, A well bred horse, that was upwards of ten years in 
my father’s stables, ridden for all purposes ; amongst others, by 
