614 Professor C. S. Sherriiifjion [April 19, 



a strong stimulus is applied contracts strongly, when a weak stimulus, 

 weakly, under a long stimulus, it contracts long, under a brief, briefly. 

 The nervous system, in making use of this muscle, wants of it just 

 such varied action as this — now weak, now strong, now brief, now 

 long, as may be suited to the act required. The little organ is 

 admirably adapted to be the animal's instrument in the world in which 

 it is placed. This muscle has its place in the economy of nature, and 

 into it it fits as a key into the lock for which it has been made. 

 Man's naive view, until somewhat recently, was that the earth and 

 the universe were made to fit him. Was the universe made to suit this 

 httle muscle, or was this little muscle made to suit the universe ? 

 The problem concerning this muscle and that concerning man are, in 

 so far, the same. Surely our answer is, that the muscle and the rest 

 of the universe fit each other because they have grown up together — 

 because they are part of one great whole ; they fit just as a lock and 

 key fit because they compose one thing ; and it is pointless to ask 

 whether the lock was made to fit the key or the key the lock. 



The ofiice of the nervous system is to co-ordinate the activities of 

 the various organs of the body, so that by harmonious arrangement the 

 power and delicacy of the animal's mechanism may be obtained to the 

 full. When reflex action withdraws the foot of a sleeping child, it is 

 not merely one such muscle as this which moves the limb but many. 

 The limb has many muscles, and even in such a simple act many 

 and many of them are employed. 



That the act occurs during sleep shows that consciousness is not 

 its necessary adjunct. A similar act can be similarly evoked in an 

 animal when the brain — the seat of consciousness — has been removed. 

 The brain can be removed under deep narcosis of chloroform 

 without any pain or feeling whatsoever. After that removal the 

 animal is no longer a sentient or conscious thing at all. Then we 

 can study in it the power of reflex action sundered from cunscient 

 and sentient life altogether. Then it is that opportunity is given 

 for further reverent analysis of those wonderful and subtle workings 

 of the nervous system which in ourselves are so difficult to unravel 

 for the very reason tliat their working goes on without appeal to, and 

 often beyond access of, the conscious self. 



When analysing the muscular action of even so simple a reflex act 

 as that of drawing up the foot, a fact which early meets the o])server 

 is that the nervous system treats whole (jroiq)s of muscles as single 

 mechanisms. In lifting the liml) it employs together muscles not only 

 of one joint of the liml), Imt of all the joints— knee, hip, ankle, etc. 

 It deals with all these muscles as if they were but one single machine. 

 If the movement is forcil)le, it throws them all into strong contraction ; 

 if weak, into weak. In the grading of the reflex action its influence 

 is graded in all these muscles alike. So also the contraction in all of 

 them is timed to begin together, to culminate together, and to desist 

 together. Further, although the movement of this lifting of the hmb 



