ON SLEEP 499 



especially systemic, nerve organisms. Moreover, during 

 these periods of sleep, and of course the " sounder " 

 physiologically they are the better, nerve energy, where 

 it has been over-expended, is renewed, if not by regenera- 

 tion, by the re-distribution of the unspent energy of the 

 idle and surcharged neurons, thus relieving the latter of 

 any unneeded explosive or potential energy, or what is 

 unrequired for their immediate functional needs, by trans- 

 ferring it to the exhausted and force-expended neurons, 

 which have been " bearing the work and worry of the 

 day." 



Sleep ! What is sleep from this point of view ? It is 

 the cessation of conscious cerebration and the controlled 

 expenditure of nerve energy, whether in. "thought, word, 

 or action," i.e. of the intellectual, sensory, volitional, and 

 motor modes of nerve energy brought about by the 

 exhaustion of that energy, in whole or in part, or by the 

 material or mechanical clogging of the generating, regu- 

 lating, and expending machinery, due to more or less 

 intense, or prolonged, action and wear and tear, and in 

 consequence, it may be, of auto-toxis, or intoxication, 

 begotten of the accumulation of effete toxic and mal-active 

 substances, and a consequent temporary paralysis cerebri. 



We again ask, What is sleep ? That is a question 

 which has aroused the curiosity and baffled the oft-tried 

 ingenuity of the human mind in every generation of the 

 race, and which still awaits an answer. The presumption, 

 or assurance, therefore, involved or implied here, in again 

 attempting an answer, may perhaps be excused on the 

 ground of the attempter's possession of the usual, if 

 not an abnormal, curiosity, and a desire, if possible, to 

 add a little more to the modicum of truth which has 

 already accumulated on the subject. 



Sleep may be further described as the cessation of the 

 function of active, or physiologico-psychological, cerebra- 

 tion in its complete systemic aspect, due to the operation 

 of an inherent property and process of inhibition possessed 

 by the individual and collective neurons, or to the exist- 

 ence in the neuronal commonwealth of a self-regulative 

 and inhibitory machinery ; or, it may be, to a combination 

 of individual and general neuronal inhibitory systems, one 



