230 



Physics of the Soil. 



earth to cover the weeds in the row. A good cultivator for 

 this kind of work is represented in Fig. 67. The levelers 

 i*epresented in the rear of the discs are intended to throw 



FIG. 69. Two good garden cultivators. 



the earth back to prevent ridging when the tool is used for 

 ordinary cultivation and ridging is not desired. 



281. Garden Cultivators. Two good forms of garden cul- 

 tivators are represented in Fig. 69, where the upper one is 

 to be used early, when the plants and weeds are small, and 

 the lower one when the harrow-stage has passed. In the 

 garden as in the field the best time to kill weeds is just as 



