COSMIC PHILOSOPHY 



accompanied by a muscular action of the stom- 

 ach that is also undulatory ; and the peristaltic 

 motion of the intestines is of like nature. The 

 blood obtained from this food is propelled not 

 in a uniform current but in pulses ; and it is 

 aerated by lungs that alternately contract and 

 expand." To this we may add that assimilation 

 is a continuous process of rhythmic interchange 

 between the molecular constituents of the vari- 

 ous tissues and of the blood by which they are 

 bathed ; that muscular action is the result of a 

 series of oscillatory movements ; and that ner- 

 vous action depends upon a quickly alternating 

 rise and fall in the chemical instability of the 

 molecules which compose the nerve-centres. 

 All these minor rhythms are as ripples upon 

 the surface of the longer rhythm constituted by 

 sleep and wakefulness. Recent researches have 

 shown that sleep itself furnishes a beautiful illus- 

 tration of the manner in which rhythm is neces- 

 sitated by the continual redistribution of forces 

 in the organism. According to the most recent 

 view, sleep is caused by a diminution in the ca- 

 pacity of the cerebral arteries, which lessens the 

 circulation of blood through the brain. It is the 

 sympathetic nerve which effects this contraction 

 of the arteries. During the day the activity of 

 the cerebrum itself supplies the stimulus which 

 causes arterial blood to flow through the head 

 in large quantities, so as to keep the vessels 

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