266 DR. PHILIP'S OBSERVATIONS ON • 



state of the stomach, from the cause just pointed out, may influence every part 

 of the nervous system ; and it appears from experiments which the Society did 

 me the honour to publish many years ago, some of which were repeated by 

 Mr. Cliff, that a powerful and sudden affection of the nervous system is 

 capable of immediately destroying the circulation in every part of the animal, 

 by instantly depriving both the heart and blood-vessels of their power. 



Here the question naturally arises. For what purpose are the vital organs 

 thus connected with every part of the brain and spinal marrow ? 



This question is answered by experiments detailed in my treatise on the Vital 

 Functions, an account of some of which appeared in the Philosophical Trans- 

 actions of 1822. From them it was found that the power of secreting surfaces 

 is deranged by abstracting from them any considerable part of the influence 

 either of the brain or spinal marrow ; and as the function of secretion is effected 

 by the action of the nerves on the blood, as appears from facts detailed in the 

 paper just referred to, and another which I had the honour to lay before the 

 Society a few weeks ago, it is evident that the presence of nervous power in 

 a secreting organ would be useless, were not the blood on which it operates 

 also supplied, and disordered if it were not supplied in due proportion ; and 

 consequently its supply varied as the supply of nervous power varies. 



We thus see not only why secreting surfaces are placed under the influence 

 of every part of the nervous system, but also why it is necessary that the san- 

 guiferous system should be under the controul of the same laws which regulate 

 the supply of nervous power. 



It appears then that by means of the system of ganglionic nerves, the in- 

 fluence of every part of the brain and spinal marrow is bestowed on secreting 

 surfaces, and on those organs by which the supply of their fluids is regulated, 

 and that this influence is necessary to their functions. But it is not the secret- 

 ing power alone that is thus placed under the influence of every part of the 

 brain and spinal marrow ; for it is a necessary inference from experiments re- 

 lated in a paper which the Society did me the honour to publish last year, 

 that the whole of those processes on which the healthy structure of the part 

 depends are under the same influence. 



The influence therefore of the whole brain and spinal marrow is thus united 

 by nerves from various parts of these organs entering ganglions and plexuses, 



