228 NECESSARY QUANTITY OF SLEEP. 



" nature's sweet restorer," though plunging the restless 

 and active powers of the soul into a state resembling as 

 nearly as we can conceive, that of annihilation, should yet 

 be attended with a pleasure from which we part with re- 

 luctance. 



Dr. B. It seems to be a law of the animal economy 

 that repose should be attended with pleasure, for the 

 same reason th'it the gratification of our appetites is. The 

 quantity of sleep required greatly varies according to age, 

 temperament and habits. In early childhood, and in the 

 second childhood of old age, where the small share of irri- 

 tability is soon exhausted, and nature demands frequent 

 repose, much of the time is spent in this state. It may 

 be considered generally, that the quantity of sleep neces- 

 sary to good health, gradually diminishes from birth till 

 the age of mature manhood ; from that period till death, 

 its necessity as constantly increases. The young stu- 

 dent knows how difficult it is for him to continue his ap- 

 plication for a space of time which the veteran scholar 

 will nearly double, without the least inconvenience. It 

 is true, when ambition or some other powerful motive 

 spurs him on, he may leave his bed early and burn his 

 lamp late, but the unhappy effects that so often follow 

 such exertions, show full well how unnatural they are. 



In maturer life when the vital powers are not so soon 

 exhausted, the system is capable of much greater exer- 

 tions. Hear the declaration of Buffon, when speaking 

 of those moments of abstraction and rapture which ac- 

 company the meditations of the great genius, and consti- 

 tute his true hours of production and composition, " I 

 have spent fourteen or fifteen hours successively, at my 

 desk, and still been in a state of pleasure." 



Emily. I have heard too that Mr. though now 



nearly seventy years old, generally spends fourteen hours 

 every day in close-study. 



Dr. B. The influer.ee of habit also, in determin- 

 ing the necessary quantity of sleep, is considerable. 



