1862.] 97 



mercury in a thermometer placed between the little and annular 

 fingers, while the others remain nearly unaffected. 



It is still more easy to ascertain this influence when the nerve is 

 paralysed by pressure. 



Thus, in the following observation, I found 



When the integuments of the little finger began to tingle Cent. 



between the roots of the little and annular fingers .... = 22'4 

 At the same time between the roots of index and median 23*4 

 When the anaesthesia over the little finger was more ad- 

 vanced and its adductor muscle somewhat paralysed be- 

 tween roots of little and annular fingers 21*4 



At the same time between index and median 22 '4 



Some minutes later between little and annular finger 21'0 



At the same time between index and median 22*3 



When the paralysis and anaesthesia were nearly complete 



between little and annular fingers 19'0 



At the same time between index and median 22*3 



The temperature of the right hand between the fingers 



remained nearly stationary 24'0 



In other experiments on compression of the ulnar nerve I have 

 observed a much greater fall of temperature as the integuments be- 

 came insensible. 



With regard to the elevation of temperature, I have never been 

 able to obtain it by compression of the ulnar nerve to the extent 

 produced by refrigeration. 



Compression of the Left Radial Nerve. 



Feb. 10, 1862. This nerve was compressed at the lower part of 

 its course at the arm, where it winds round the humerus to its ex- 

 ternal side. This was effected simply by pressing the outer part of 

 the arm against the padded arm of a chair. 



In about half an hour the skin of the back of the hand had be- 

 come somewhat insensible, and the muscles of the forearm so much 

 weakened that the hand dropped by its own weight. These 

 symptoms continued to increase until the extensor muscles of the 

 forearm were quite paralysed. Examination three-quarters of an 

 hour after the commencement of the experiment gave as follows : 



VOL. XII. H 



