1 1 8 Traces of Unity in 



Next in order have to be named Glisson, Haller, and 

 tlte Brown, known as the author of the Brunonian system 

 of medicine, men whose speculations form the basis of 

 the doctrine of vital movement now in favour. 



Glisson, an eminent professor at Cambridge in his 

 day, was the first to advance the present doctrine of 

 muscular irritability. He asserted that there was in 

 muscle a specific vital property, to which he gave this 

 name, and that contraction was due to this property 

 being in some way put in action. 



Haller expanded this idea, and drew for the first time 

 a line of distinction between the special vital property of 

 muscle and the special vital property of nerve. He 

 retained the name of irritability for this property in 

 muscle ; he gave the name of sensibility to this property 

 in nerve. Each property was something vital, something 

 departing at death, and therefore in nowise akin to any 

 power in inanimate nature, The property was a life of 

 which muscular contraction and nervation were acts. 



Brown, starting from this point, added another idea 

 that of stimulation. Everything acting upon the vital 

 property of irritability or sensibility (to which he gave 

 the common name of excitability), according to him 

 acted as an excitant or stimulus, Action is caused by 

 a process of stirring-up, as it were, the capacity for action 

 being asleep, or at rest, until it is so stirred-up. The 

 idea would seem to be none other than that all vital 

 movement in its nature is identical with that which is 

 produced by teasing a sleeping man until he wakes up 

 and strikes about him in anger. 



And this doctrine of vital motion, which thus took 

 form in the speculations of Glisson, Haller, and Brown, is, 

 with little change, the doctrine at present in favour. 

 In point of fact, the position taken at present has but 



