Proceedings of the Royal Society of Edinburgh. 405 
trine here maintamed, and that of Haller and his followers, 
which has befen lately espoused, and strongly supported by Dr 
Wilson Philip. 
The observations made by this last gentleman, on the diffe- 
rent effects of physical agents applied to large and to small por- 
tions of the brain, on the two great classes of muscular organs, — > 
the former affecting chiefly the actions of the involuntary, and 
the latter, particularly when touching the origins of the nerves, 
exciting the voluntary muscles,— have induced the author of 
this paper^ to add one to the many conjectures already hazard- 
ed, in regard to the use of the ganglia, and of the great sym- 
pathetic nerve, from which the involuntary muscles are chiefly, 
and many of the voluntary are partly supplied. These he sup- 
poses to concentrate, and to increase the influence, upon the or- 
gans which they supply, of changes which extend to large por- 
tions of the nervous system ; and he gives reasons for conjec- 
turing, that changes of this kind may be produced on the ner- 
vous system, by those sensations, emotions, and passions of 
mind, which are known particularly to affect those muscles, 
both voluntary and involuntary, which are supplied with nerves 
from the ganglia; and thence concludes, that the transmission 
of the effect of such changes, may be the principal object of 
this arrangement of nerves. 
In regard to the connection of the nervous system with secre- 
tion, the author contends, in opposition to several eminent phy- 
siologists, 1. That the nature of the actions of nerves is proba- 
bly not galvanic ; and, % Even if they be galvanic, that these 
actions appear, from facts already known, not to be essentially 
concerned in secretion. And in regard to its connection with 
animal heat, he contends, 1. That no necessary connection be- 
tween the evolution of animal heat, and any influence that can 
be derived from the nerves, has been established by the recent 
inquiries on this subject ; andj S. That the other cause, com- 
monly assigned since the time of Black and Crawford, for this 
function of animals, certainly exists, and is adequate to the ex- 
planation of the phenomena. 
If it can be ascertained, by this kind of examination of the 
facts ascertained in this department of physiology, what func- 
tions are merely subject to the occasional controul, and what are 
I 
