EX VI RIB US VIVIMUS. 



chapters on Genesis and on Multiplication, estab- 

 lishes certain laws of correspondence, which, together 

 with the facts he so adequately cites, have the closest 

 bearing on the antecedents of longevity. Never- 

 theless it is to be noted that the term 'longevity' 

 is not once used in these chapters, nor is the dura- 

 tion of individual life discussed directly at all. Did 

 the nature of this essay permit, it would be perhaps 

 the most satisfactory way of treating the question 

 of longevity, to assume the contents of Mr. Spencer's 

 volumes and to write a last chapter on the Duration 

 of Individuals. This is not, however, the form which 

 it is deemed right to adopt upon the present occasion, 

 though frequent reference to and use of the views 

 of this most eminent philosopher will be made. 



Having dismissed the subject of books, let us con- 

 sider for a moment the nature of the data which 

 are available with regard to the duration of life. 

 We shall find that the paucity and uncertainty of 

 observations on this class of facts is something really 

 extreme. Lord Bacon, in his ' Historia Vitse et 

 Mortis,' makes a remark which is true to this day : — 

 ' De diuturnitate, et brevitate vitae in animalibus 

 tenuis est informatio, quse haberi potest ; observatio 

 negligens ; traditio fabulosa ; in cicurribus vita 

 degener corrumpit ; in sylvestribus injuria cceli in- 

 tercipit.'^ To begin with man himself, we have sta- 



' Montagu's edition, 1828, vol. a. p. 134. 



