764 THE POPULAR SCIENCE MONTHLY. 



of life among its members is decidedly low, a fact which can be 

 easily accounted for. Broken rest, hard work, anxieties, exposure 

 to weather and to the risks of infection can not fail to exert an 

 injurious influence upon health. No definite conclusions can be 

 arrived at with regard to the average longevity of literary and 

 scientific men, but it might be supposed that those among them 

 who are not harassed by anxieties and enjoy fair health would 

 probably reach old age. As a general rule, the duration of life is 

 not shortened by literary pursuits. A man may worry himself 

 to death over his books, or, when tired of them, may seek recrea- 

 tion in pursuits destructive to health ; but application to literary 

 work tends to produce cheerfulness, and to prolong rather than 

 shorten the life even of an infirm man. In Prof. Humphry's 

 " Report on Aged Persons," containing an account of eight hun- 

 dred and twenty-four individuals of both sexes, and between the 

 ages of eighty and one hundred, it is stated that forty-eight per 

 cent were poor, forty-two per cent were in comfortable circum- 

 stances, and only ten per cent were described as being in affluent 

 circumstances. • Dr. Humphry points out that these ratios " must 

 not be regarded as representing the relations of poverty and afflu- 

 ence to longevity, because, in the first place, the poor at all ages 

 and in all" districts bear a large proportion to the affluent ; and, 

 secondly, the returns are largely made from the lower and middle 

 classes, and in many instances from the inmates of union work- 

 houses, where a good number of aged people are f ound." It must 

 also be noticed that the " past life-history " of these individuals 

 showed that the greater proportion (fifty-five per cent) " had lived 

 in comfortable circumstances," and that only thirty-five per cent 

 had been poor. 



Merely to enumerate the causes to which longevity has been 

 attributed in attempting to account for individual cases would be 

 a task of some magnitude ; it will be sufficient to mention a few 

 somewhat probable theories. Moderation in eating and drinking 

 is often declared to be a cause of longevity, and the assertion is 

 fully corroborated by Dr. Humphry's inquiries. Of his fifty-two 

 centenarians, twelve were recorded as total abstainers from alco- 

 holic drinks throughout life, or for long periods ; twenty had 

 taken very little alcohol ; eight were reported as moderate in their 

 use of it ; and only three habitually indulged in it. It is quite 

 true that a few persons who must be classified as drunkards live 

 to be very old ; but these are exceptions to the general rule, and 

 such cases appear to be more frequent than they really are, because 

 they are often brought to notice by those who find encouragement 

 from such examples. The habit of temperance in food, good 

 powers of digestion, and soundness of sleep are other main char- 

 acteristics of most of those who attain advanced years, and may 



