A N D D E A T H. 47^ 



a fhort time, penfhcs much fooner than thofe 

 which are longer in arriving at that period. In 

 animals, as well as vegetables, the longitudinal 

 growth is firft liniihed. Man grows in ftature 

 till he be 16 or 18 years of age ; but his body 

 is not completely unfolded in thicknefs before 

 that of 30. Dogs acquire their full length in 

 lefs than one year j but their growth in thick- 

 nefs is not liniihed till the fecond year. A man, 

 who grows 30 years, lives till 90 or 100; and a 

 dog, whofe growth terminates in two or three 

 years, lives only 10 or 12. The fame obferva- 

 tion may be applied to moft animals. Fifhes 

 continue to grow for a great number of years ; 

 they accordingly live for centuries; becaufe 

 their bones never acquire the denfity of thofe of 

 other animals. When we give the particular 

 hiRory of animals, we fhall examine whether 

 there be any exception to this rule, which Na- 

 ture feems to follow in proportioning the du- 

 ration of life to the time of growth, and whether 

 crows and flags llvefo long as is commonly ima- 

 gined. But it may be laid down as a general 

 fad, that large animals live much longer than 

 imall animals, becaufe they require more time 

 to finlfh their growth. 



Thus the caufes of our dijfolution are inevi- 

 table; and it is equally impofliblc to retard that 

 fatal period, as to change theeftablilhed laws of 

 Nature. The ideas of thofe vifionaries, who 

 conceived the pofTibility of perpetuating human 



life 



