164 BULLETIN OP THE UNIVERSITY OF WISCONSIN. 



while guiding the destinies of nations to survive o.n a very lim- 

 ited amount of sleep. Every one knows of Napoleon's capacity 

 in this direction. On the other hand, Gladstone is said to have 

 required seven hours' sleep quite regularly throughout his public 

 life. In our own country there is a president of a great uni- 

 versity who is reported to get along with at most four hours of 

 sleep, and on occasions he is able to do well on two hours. But 

 for the majority of individuals it is probable that somewhere 

 near eight hours is essential. 1 Cowles, 2 Beard, 3 Mills, 4 and 

 other writers upon nervous exhaustion are quite insistent upon 

 this amount for all people; and while it may certainly be im- 

 possible for one individual to survive on what another will thrive 

 on, yet it is probable that a third of the day spent in sleep could 

 not but be of advantage to every person and in no case could 

 it be a detriment. 



The majority of our students give the required number of houra 

 to sleep. Two hundred and thirteen reported that they devoted 

 eight hours to this purpose ; fifty-eight spend seven hours ; thirty- 

 four, nine hours ; one, ten hours ; four, six hours ; while only two 

 spend five hours. If their sleep be sound then our students 

 should on the whole be well provided for in this respect. But 

 in many cases people feel they are complying with all the re- 

 quirements if they simply lie in bed. However, in order that 

 sleep be fully reparative it ought to be peaceful and dreamless ; 

 otherwise the cerebral areas concerned in conscious mental life 

 are active and energy is being dissipated. That one may secure 

 this perfect rest his sleeping environment must be quite -free 

 from noise. Noise has a peculiar effect upon one asleep ; even 

 the slightest auditory stimulus seems to produce a waking re- 

 action. It appears that there is in the human soul a sort of 

 memory of earlier racial experiences where noise was a most 

 significant affair; an animal that could not awaken instantly 

 upon sounds of howling or cracking or crunching or breathing 



l cf. Kotelmann, School Hygiene, pp. 187 and 225-231. 

 *op. cit. 

 *op. cit. 



4 Mental Over-work and Premature Disease Among Public Men. Smithsonian 

 Inst., Lower Lectures, No. IX. 



