* 



CLAUDE BERNARD 



67 



paralysed limb was chilled, I supposed the sympa- 

 thetic nerve to be paralysed, as well as the motor 

 nerves ; while in the paralysed limbs that were not 

 chilled, the sympathetic nerve had retained its 

 function, the systemic nerves alone having been 

 attacked. 



"This was a theory, that is to say, an idea 

 leading me to make experiments ; and for these 

 experiments I must find a sympathetic nerve-trunk 

 of sufficient size, going to some organ that was 

 easy to observe, and must divide this trunk to see 

 what would happen to the heat-supply of the organ. 

 You know that the rabbit's ear, and the cervical 

 sympathetic nerve of this animal, offered us the 

 required conditions. So I divided the nerve ; and 

 immediately my experiment gave the lie direct to 

 my theory — Je coupai done ce filet et aussitot £ex- 

 pdrience donna a mon hypothese le plus dclatant 

 ddmenti. I had thought that the section of the 

 nerve would suppress the function of nutrition, of 

 calorification, over which the sympathetic system 

 had been supposed to preside, and would cause the 

 hollow of the ear to become chilled ; and here was 

 just the opposite, a very warm ear, with great 

 dilatation of its vessels. 



" I need not remind you how I made haste to 

 abandon my first theory, and gave myself to the 

 study of this new state of things. And you know 

 that here was the starting-point of all my researches 

 into the vaso-motor and thermic system ; and the 

 study of this subject is become one of the richest 

 fields of experimental physiology. " 



Waller, in 1853, studied the vaso-motor centre 

 in the spinal cord; and Schiff, in 1856, found evi- 

 dence of the existence of two kinds of vaso-motor 



