346 
DR. PHILIP ON THE POWERS OF LIFE. 
nerves, but which appear to have no relation to any nervous filaments hut those of 
the particular nerve to which they belong 1 . It is therefore necessary that I should 
define the sense in which I use the terms ganglion and ganglionic nerve. By gan- 
glion, I mean a nervous protuberance which receives nerves from different sources ; 
and by ganglionic nerve, a nerve which either enters or sends branches to such gan- 
glions, or proceeds from them, whether it have or have not any such protuberance 
belonging to itself. It may be stated however that there is reason to believe that 
all nerves, having such protuberances, contribute towards forming the ganglions in 
the sense in which I use the term*. 
One of the most evident peculiarities of the ganglionic nerves, in the sense in which 
I use the term, is, that while the cerebral and spinal nerves supply the sensitive organs 
and the muscles of voluntary motion, the ganglionic nerves supply the muscles of 
involuntary motion and the other vital organs. 
Haller, finding that the heart cannot be influenced through its nerves in the 
same way as a muscle of voluntary motion, was led to the conclusion that the 
former cannot be directly influenced through the nerves. But M. Le Gallois has 
shown that he was deceived in this inference, the heart being immediately subject 
to the influence of the spinal marrow ; and the latter author further inferred from 
his experiments that the spinal marrow is not only capable of directly influencing 
the heart through its nerves, but that, through the same channel, it bestows on 
both the heart and blood-vessels all their powers ; an inference refuted both by ex- 
periments already referred to, and others, an account of which appeared in the Phi- 
losophical Transactions for 1815 and has since been republished in my Inquiry into 
the Laws of the Vital Functions ; and some of which were at the request of the Royal 
Society repeated with the same results by Mr. Clift, Mr. Clift’s confirmation of 
them being published in the same volume of the Transactions. 
The circumstance of the brain and spinal marrow only, as we shall find, influencing 
the heart under peculiar circumstances is probably the cause of the fact ascertained 
by Haller, that it cannot be excited through its nerves in the same way as a muscle 
of voluntary motion, an observation which applies to all muscles of involuntary mo- 
tion, a want of attention to which has misled some physiologists-^. 
From the whole of the experiments which have been referred to, it appears, on the 
one hand, that neither the brain nor spinal marrow bestows any power on the heart 
or vessels ; but, on the other, that each of the former organs is equally capable of di- 
rectly influencing both, (the vessels even to their utmost extremities,) and that, not only 
by exciting their powers, but also by impairing and even wholly destroying them, ac- 
cording to the nature and power of the agent operating on the brain or spinal marrow ; 
* See a paper on the functions of the nervous system in the Philosophical Transactions for 1829, which 
was republished in my treatise On the Nature of Sleep and Death. 
t See my reply to MM. Breschet and Milne-Edwards in the Philosophical Transactions for 1833, en- 
titled “ Some Observations relating to the Function of Digestion.” 
