(455 ) 



SMITH S SUBSOIL-PLOUGH. 

 (See p. 450.) 



RACKHEATH SUBSOIL-PLOUGH. 



&quot; This performs the operation of subsoil ploughing, to the depth of from ten to 

 sixteen inches below the surface, and, when preceded by the common plough, 

 which is the plan recommended, the depth reached below the surface ground is 

 just so much the more than the first plough effects.&quot; 



RACKHEATH SUBTURF-PLOUGH. 



&quot;This plough answers admirably for under-ploughing grass lands, and is made 

 into a subturf-plough by changing the wheel gear in front to that of a carriage 

 and two wheels.&quot; 



