10 HISTORY OF 



at last be fatal. By these means, however, they 

 continue several days without eating, cheerfully 

 bearing such extremes of fatigue and watching, 

 as would quickly destroy men bred up in a great- 

 er state of delicacy. For those arts by which we 

 learn to obviate our necessities, do not fail to un- 

 fit us for their accidental encounter. 



Upon the whole, therefore, man is less able to 

 support hunger than any other animal ; and he is 

 not better qualified to support a state of watchful- 

 ness. Indeed, sleep seems much more necessary 

 to him than to any other creature ; as, when 

 awake, he may be said to exhaust a greater pro- 

 portion of the nervous fluid, and, consequently, 

 to stand in need of an adequate supply. Other 

 animals, when most awake, are but little removed 

 from a state of slumber; their feeble faculties, 

 imprisoned in matter, and rather exerted by im- 

 pulse than deliberation, require sleep rather as a 

 cessation from motion than from thinking. But 

 it is otherwise with man : his ideas, fatigued with 

 their various excursions, demand a cessation, not 

 less than the body, from toil ; and he is the only 

 creature that seems to require sleep from double 

 motives ; not less for the refreshment of the men- 

 tal, than of the bodily frame. 



There are some lower animals, indeed, that 

 seem to spend the greatest part of their lives in 

 sleep ; but, properly speaking, the sleep of such 

 may be considered as a kind of death, and their 

 waking, a resurrection. Flies and insects are 

 said to be asleep, at a time that all the vital mo- 

 tions have ceased ; without respiration, without 



