90 VEGETABLE SUBSTANCES. 



again admitted, and remains covering the surface until 

 the grain is actually ripened. 



The rice harvest in the United States usually com- 

 mences at the end of August, and extends through 

 the entire month of September, or even somewhat 

 later. The reaping is performed with a sickle by 

 male negroes, and these are followed by females, who 

 collect the rice into bundles. 



This cultivation is found to be extremely unhealthy 

 to the negroes employed in its prosecution. The 

 alternate flooding and drying of the land in so hot a 

 climate, were natural evaporation proceeds with great 

 rapidity, must necessarily be prejudicial to health. 

 To avoid exposure to this unwholesome atmosphere, 

 the whole white population abandon the low grounds 

 to the care of negro cultivators. The mortality thus 

 occasioned among the labourers in rice districts is so 

 great, that while the general increase of population in 

 the States exceeds by far that realized in the older 

 settled countries of Europe, fresh supplies of negro 

 slaves must continually be brought, to repair the waste 

 of life, from the more northern slave states of the 

 Union. 



The cultivation of rice is very extensively and 

 successfully carried on in the rich meadows of 

 Lombardy, which can be irrigated by the waters 

 of the Po. The meadows chosen for the purpose are 

 perfectly flat. After the seed is sown, the water is 

 turned on and allowed to cover the surface to the 

 depth of several inches during the whole course of its 

 growth, and until the rice is ripe. Three crops are 

 taken successively from the ground in this manner 

 without manuring ; but the soil is then so far exhaust- 

 ed, that it must be manured and planted for a time 

 with other crops, before another succession of rice 

 harvests can be drawn from it. 



This system of agriculture proves the most profit- 



