416 KATURAL AND CIVIL 



CHAPTER XIL 



State of Society. Pop ulation : Cmv^s on 

 which this de/wnds, the mean Pet-iod of Human 

 Life in the Aaierican States, Period ofdoiib- 

 Img in Fenndtit, comparative Vicxv of Popula- 

 tion in 7iew and old Cou?itries, 



POPULATION depetids upon two 

 g^ileral causes, itlie origiiial laws of nature, and 

 the state of society. Li the original coiistitutioa 

 of animals, the Author of Natui'e has estabhshed 

 certain laws respecting their increase, and mul- 

 tiplication, whii.'h cannot be exceeded. These 

 laws relate chiefiy to the age at which the ib- 

 male becomes capable of bearing fruit, the 

 numbers that may. be produced at one birth, 

 the time that must intervene between one birth 

 and another, and the age at which the female 

 will cease to be prolific. The kws of nature 

 respecting each of these particulars, considered 

 Aviih respect to the human raet, are much af- 

 fected by climate ;,and are every where subject 

 to universal and constant observation. But they 

 are so far from being, accurately known, or as- 

 certained, that v.'hoever shall attempt to make a 

 computation upon cither, or all of them, will 

 iiad that not one of these periods has .been 

 •marked by oiiservation ; and that the mean pe- 

 riod required by nature for these purposes, is 

 tct unknown in ev( ry country and climate. 



The increase of mankind, thus confined 

 within certain limits by 'nature, is also very 

 much afixictcd by tlie state of society. The 



