OF NATURAL HISTORY. 287 



the parts is evidently improved, and the teeth begin to flioot. The 

 growth of the whole body, as well as the ftrcngth and beauty of its 

 form, gradually advance to perfection till the fixth or feventh year, 

 when another change takes place. At this period, the firft fet of 

 teeth are fhed, and are replaced by new ones. From boyhood to 

 puberty, the fize of the body, and of its different members, increafe. 

 When the age. of puberty arrives, fevcral important changes are pro- 

 duced in the fyftem of both males and females. The beard now 

 makes its appearance ; the dimenfions of the body, in moft indivi- 

 duals, are fuddenly augmented ; and both fexes become capable of 

 multiplying the fpecies. From this period, to the age of twenty- 

 five or thirty, the mufcles fwcll, their interfaces are filled with fat, 

 the parts bear a proper proportion to each other, and man may now 

 be confidered as a perfed animal. In this ftate of bodily perfedio;a 

 and vigour, he generally remains till he reaches his fiftieth year. 

 Then a new but a gradual change begins to appear. From the 

 fiftieth year to the age of feventy or eighty, the powers of the body 

 decline in their ftrength and adivity. The mufcles lofe their fpring 

 and their force. The vigour of manhood is no longer felt; and the 

 withered decrepitude of old age is facceeded by death, its unavoid- 

 able confequence. 



The mind of man undergoes changes as well as his body. The 

 tafte, the appetites, and the difpofitions, are in perpetual fluduation. 

 How different is the tafte of a child from that of a man ? Fond of 

 gewgaws and of trifling amufements, children frolic away their time 

 without much thought or refledion. When advancing toward pu- 

 berty, their difpofitions and defires fuffer a gradual mutation. New 

 inftinfts are unfolded, and a fenfe of propriety begins to be per- 

 ceived. They defpife their former occupations and amufements ; 

 and different fpecies of objeds follicit and obtain their attention. 

 Their powers of refledion are now confiderably augmented ; and 

 I both. 



