348 Of the Checks to Population Bk. ii. 



have not produced, he should rest the whole proof 

 of the depopulation of the Pays de Vaud on the 

 proportion of births. There is no good reason for 

 supposing that this proportion should not be dif- 

 ferent at different periods, as well as in different 

 situations. The extraordinary contrast in the fe- 

 cundity of the two parishes of Leyzin and St. 

 Cergue depends upon causes within the power of 

 time and circumstances to alter. From the great 

 proportion of infants which was found to grow up 

 to maturity in St. Cergue, it appeared that its na- 

 tural healthiness was not much inferior to that of 

 Leyzin.* The proportion of its births to deaths 

 was 7 to 4 ;f but as the whole number of its inha- 

 bitants did not exceed 171, it is evident that this 

 great excess of births could not have been regu- 

 larly added to the population during the last two 

 centuries. It must have arisen therefore either 

 from a sudden increase of late years in the agri- 

 culture or trade of the parish, or from a habit of 

 emigration. The latter supposition I conceive to 

 be the true one ; and it seems to be confirmed by 

 the small proportion of adults which has already 

 been noticed. The parish is situated in the Jura, 

 by the side of the high road from Paris to Geneva, 

 a situation which would evidently tend to facili- 

 tate emigration ; and in fact, it seems to have acted 

 the part of a breeding parish for the towns and flat 

 countries ; and the annual drain of a certain por- 



* Memoires, &c. par la SocieteEcon. de Berne. Annce 1766, 

 table xiii. p. 120. 

 f Td. table i. p. 11. 



