THE ART OF PROLONGING LIFE. 763 



one fourth of our population attains the former age, and that only 

 about fifteen in one hundred thousand become centenarians. It 

 is beyond the scope of this article to discuss the causes of prema- 

 ture mortality, but the conditions favorable to longevity, and the 

 causes to which length of days has been assigned, are closely con- 

 nected with its subject. 



A capability of attaining old age is very often handed down 

 from one generation to another, and heredity is probably the 

 most powerful factor in connection with longevity. A necessary 

 condition of reaching advanced age is the possession of sound 

 bodily organs, and such an endowment is eminently capable of 

 transmission. Instances of longevity characterizing several gen- 

 erations are frequently brought to notice. A recent and most 

 interesting example of transmitted longevity is that of the veteran 

 guardian of the public health, Sir Edwin Chadwick, who was 

 entertained at a public dinner a few weeks ago on the occasion of 

 his reaching his ninetieth year. He informed his entertainers 

 that his father died at the age of eighty-four, his grandfather at 

 ninety -five, and that two more remote ancestors were centenarians. 



It is difficult to estimate the influence of other contingencies 

 which affect longevity. With regard to sex, Hufeland's opinion 

 was that women were more likely than men to become old, but 

 that instances of extreme longevity were more frequent among 

 men. This opinion is to some extent borne out by Dr. Humphry's 

 statistics : of his fifty-two centenarians, thirty-six were women. 

 Marriage would appear to be conducive to longevity. A well- 

 known French savant, Dr. Bertillon, states that a bachelor of 

 twenty -five is not a better life than a married man of forty-five, 

 and he attributes the difference in favor of married people to the 

 fact that they take more care of themselves, and lead more regu- 

 lar lives than those who have no such tie. It must, however, be 

 remembered that the mere fact of marrying indicates superior 

 vitality and vigor, and the ranks of the unmarried are largely 

 filled by the physically unfit. 



In considering occupations as they are likely to affect longev- 

 ity, those which obviously tend to shorten life need not be con- 

 sidered. With respect to the learned professions, it would appear 

 that among the clergy the average of life is beyond that of any 

 similar class. It is improbable that this average will be main- 

 tained for the future ; the duties and anxieties imposed upon the 

 clergy of the present generation place them in a very different 

 position from that of their predecessors. Among lawyers there 

 have been several eminent judges who attained a great age, and 

 the rank and file of the profession are also characterized by a 

 decided tendency to longevity. The medical profession supplies 

 but few instances of extreme old age, and the average duration 



