437 



of the lower part of the ear. The feelings in fact resemble those 

 experienced in ordinary cases of blushing. 



In my observations on compression of the vago-sympathetic, I 

 found that the above-mentioned auricular symptoms are more un- 

 certain than those affecting the organs controlled by the vagus. 

 Thus in the same individual where six observations were made suc- 

 cessively at about an interval of an hour between each, dyspnoea, 

 irregularity of the heart's action, and uneasiness of the stomach were 

 produced on each occasion, while the ear-symptoms were obtained 

 twice out of the six, and lasted but a few minutes after removal of 

 the pressure. 



On the other hand, sometimes the auricular symptoms predominate, 

 whilst the others are scarcely perceptible. 



Although the auricular symptoms are certainly due to the influence 

 of some branch of nerve, we find considerable difficulty when we 

 endeavour to ascertain the exact branch that is affected, as besides 

 the vascular branches of the cervical sympathetic which exist over 

 the part compressed, we have also the auricular branches of the 

 cervical plexus close by, which may likewise give rise to the symptoms 

 in question, either by their direct influence or by reflex action. 



For many reasons, which I will not enter upon at present, I have 

 come to the conclusion that most, if not all of the symptoms produced 

 by compression of the vagus are the result of reflex action in all the 

 nerves governing the organs affected, viz. heart, lungs, stomach, &c. 

 I have arrived at the same conclusion respecting the mode of pro- 

 duction of the auricular symptoms, viz. that they are reflex. As 

 the complex arrangement of the nerves in the neck prevented my 

 obtaining any precise knowledge of the nerve acted upon, I was led 

 to make a careful study of the effects of various agents on those 

 nerves which are more accessible to examination, in order to ascer- 

 tain how far the spinal nerves distributed to other parts are suscep- 

 tible of giving rise to the same symptoms as those experienced in the 

 ear. 



My present experiments have been made chiefly on the ulnar and 

 internal popliteal nerves, but it is not my intention on this occasion 

 to describe them in detail ; I shall accordingly state only the leading 

 results, and for the present shall confine myself to those obtained 

 with the ulnar nerve. 



