PKBPARATION Or THE SOIL, OR TILLAGE. 



119 



by hand entirely, and immediately afterwards the hoe- 

 ing commences. This hoeing is done with a mechani- 

 cal device approaching within a short distance of the 

 plant, and is repeated as often as possible, until the 

 weeds are no longer to be dreaded. When the roots are 

 matured the harvesting can be done with a plough, 

 leaving just sufficient earth to keep the root in a verti- 

 cal position. They can then be extracted by hand with 

 the greatest ease, in soils of the closest texture. 



To make more apparent the advantages here gained, 

 we will suppose two beds (see fig. 24), AB and CD 



Fijg;. 24. 



LSW 



Showing the shape of the hill before and after the roller has 

 passed npon the same. 



the distance between each representing the stratum in 

 which the root will grow to advantage; below G D it 

 cannot for various reasons penetrate. The dotted line 

 represents the hill produced after one ploughing, and 

 the other, or the black undulated, the final one, E M, 

 represents the portion above the first level, and E 8 

 the height of soil that has become loosened by this 



