A HISTORY OF SCIENCE 



and the inhibitory influence of one centre over another 

 in the central nervous mechanism. 



THE BRAIN AS THE ORGAN OF MIND 



These studies of the psychologists and pathologists 

 bring the relations of mind and body into sharp relief. 

 But even more definite in this regard was the work of 

 the brain physiologists. Chief of these, during the 

 middle period of the century, was the man who is some- 

 times spoken of as the "father of brain physiology," 

 Marie Jean Pierre Flourens, of the Jardin des Plantes 

 of Paris, the pupil and worthy successor of Magendie. 

 His experiments in nerve physiology were begun in the 

 first quarter of the century, but his local experiments 

 upon the brain itself were not culminated until about 

 1842. At this time the old dispute over phrenology 

 had broken out afresh, and the studies of Flourens 

 were aimed, in part at least, at the strictly scientific in- 

 vestigation of this troublesome topic. 



In the course of these studies Flourens discovered 

 that in the medulla oblongata, the part of the brain 

 which connects that organ with the spinal cord, there 

 is a centre of minute size which cannot be injured in 

 the least without causing the instant death of the ani- 

 mal operated upon. It may be added that it is this 

 spot which is reached by the needle of the garroter in 

 Spanish executions, and that the same centre also is 

 destroyed when a criminal is "successfully" hanged, 

 this time by the forced intrusion of a process of the sec- 

 ond cervical vertebra. Flourens named this spot the 

 "vital knot." Its extreme importance, as is now un- 

 derstood, is due to the fact that it is the centre of nerves 



270 



