SLEEP. 605 



fact is explained by the intervertebral substances recovering 

 their elasticity during the removal of pressure in the night. 



Too much sleep produces headach, heaviness, and dulness : 

 too little, feebleness, intellectual and muscular; thinness; 

 indifference of the feelings, so that elephants are tamed by being 

 prevented from sleeping ; headach, and various unpleasant feel- 

 ings in the head, chilliness and feverishness, and at length an 

 inflammatory state of the brain. Studious young men too fre- 

 quently disregard the law of nature, that a certain quantity 

 of sleep is requisite for cerebral and general vigour. They 

 fancy that far less sleep than people usually take is sufficient; 

 and instead of eight hours, which most require, especially in 

 youth, take but six, or even fewer. The result of this is sooner 

 or later felt severely ; study becomes more and more difficult, 

 and, at last impossible ; constant uneasiness, tension, pain, heat, 

 throbbing in the brain are experienced ; perhaps sleep becomes 

 very difficult ; general weakness is felt, and too often inflam- 

 mation of the brain, or typhus, occur, or some other disease, 

 the causes of "which would have been inoperative but for the 

 exhausted and excited condition of the system to which they 

 were applied. So many of the best of our young men fall 

 into these circumstances every winter, and thus, if they hap- 

 pily do not die, lose eventually more time than they had stolen 

 from sleep, to say nothing of the minor efficiency of their exer- 

 tions while they can study than if they thoroughly refreshed 

 themselves by a natural allowance of repose, that I find it a 

 duty earnestly to point out this at the beginning of every 

 session in University College ; to urge that all excess, how- 

 ever free from vice, and even if it proceed from virtuous feel- 

 ings, is followed by bad consequences ; and I can with truth 

 add that such is the industry and thirst for knowledge and 

 intellectual distinction, such the correctness and good feeling of 

 the very large majority, that I never spend more than a moment 

 in guarding the freshmen against idleness, vice, and bad practices. 

 There can be no question that study after repose is more 

 efficient than before it. The brain must be more vigorous when 

 refreshed than after the excitement of the day. Many prefer 

 night study, and in the winter it is more convenient ; but, in the 



n Dr. Macnish, p. 38. 



