EXTRACT XLVI. 

 ON SLEEP. 



SYSTEMIC nerve force cannot be continuously discharged 

 by the nerve-force-producing agencies, and the process is, 

 therefore, interrupted by repose or sleep, in which both 

 the wasting results of material tear and wear and dynamic 

 loss are made good, and the storage capacity, material 

 and dynamic, of each neuron, and system of neurons, 

 renewed and secured in equipoised and non-explosive 

 proportions, the empty or exhausted being, it may be to 

 some extent, supplied from the full, or plethoric, and a 

 non-explosive medium, and smoothly working condition 

 maintained. Thus the continuance of the power of 

 sustained brain work is secured by periods of redistri- 

 bution, as well as reproduction of nerve force or energy, 

 and by the removal of waste or effete material products, 

 and the supply of fresh materials to take the place of 

 these waste or effete products during the daily recurring 

 intervals of sleep, when the presiding ego itself retires 

 for some repose behind the barriers of its material impedi- 

 menta, inhibited for the time being from the world of 

 sense and time by the idle and exhausted machinery which 

 it has ceased to animate from the lack of nerve energy or 

 power and the accumulation of disintegrated matter. 



During the intervals of sleep the psychic, sensory, and 

 motor neurons cease working, while the sympathetic, or 

 truly trophic, nervous system continues active, directing 

 the removal of debris, laying down new materials where 

 required by the incidence of waste, and " burnishing up" 

 the complex machinery of the whole vital, but more 



