Automatic Action of the Cerebrum. 839 



forgotten. Mnsdc reading also depends upon the principle that the idea 

 which moves the muscle can form the motor combination necessary to 

 stimulate the contraction without arousing consciousness of it. Even 

 when we are on the alert to prevent it, our muscles of expression are 

 wry apt to betray us from the unconscious stimulation of cerebral 

 senses. Our brain is full of unconscious or passive memories of detail 

 which we use every hour, and could not do without. B} T these we go 

 ahead and do everything, and yet we are generally unable to tell how. 

 Who can tell how lie played a Jews-harp, what muscles he moved when 

 he sp'oke, or wrote, or sung, or how widely his mouth opened when he 

 called to his friend across the street ? Yet the memory of all these de- 

 tails of muscle movement are in the brain, or else we could never (in 

 one trial) make the right motion to produce the effect. 



A story is told of a swan which came daily at a certain hour and 

 tapped at the door of a cottage where it received food ; also a dog 

 which was accustomed to be washed regularly, once a fortnight, to its 

 great dislike, and which got to running away on the washing day to avoid the 

 ordeal. We hear of horses, dogs, and other animals that know when Sunday 

 comes. These cases show an instinctive measurement of time, that is a 

 measurement by means of habit. We may say the swan got hungry about 

 that time of day, and its hunger prompted the action. True, but to be 

 hungry at a particular time of day is largely a matter of habit. Men 

 of regular habits of occupation generally get hungry at the same time 

 daily. This involves physiological processes which follow the same 

 routine daily. There must be a regular succession of actions in the 

 stomach, glands and intestines, which together complete a cycle ; and 

 when it is completed, the first term of a new C} r cle is reached, namely a 

 condition of the stomach which arouses sensation. The automatic suc- 

 cession of the actions afford an unconscious measurement of time. 

 That is. we are not conscious of the measurement while it is going on 

 but only when it is completed. That the organs do thus measure time, 

 is proved by the further fact that they can be habituated to a new rou- 

 tine. Thus some people eat three meals a day in summer and only two 

 in winter. After the change is made to the winter rule there will for a 

 while be a sensation of "goneness" about noon, but after a time this 

 is postponed to suit the new routine. Idiots are usually strongly bound 

 to habit and subject to the unconscious measurement of time, by the 

 automatic routine action of organs, and become uneasy unless the same 

 habitual performances are gone through with every day at about the 

 same time. Sometimes a pretense of doing it will satisfy. 



When a person upon going to sleep charges his brain to wake him at 

 a certain hour, as many persons have the power to do, provided the at- 

 tempt is fortified by habit, we are bound to conclude that some sort of 



