1 10 THE OLIVER PLOW BOOK 



board, consequently, a portion of the furrow is not cut 

 entirely off. The mouldboard pushes the cut part of 

 the furrow solidly against the preceding furrow, shaping 

 the furrow to leave the top diamond shaped, and drain- 

 age facilities on the bottom. 



Illustration M 



Illustration M shows a chilled bottom made for 

 handling all kinds of gritty, sandy soils, and also clay 

 lands that are not sticky. This bottom is made with a 

 sloping landside. When the plow picks up the dirt to 

 turn it over, the lower outside edge of the furrow slice 

 acts as a fulcrum over which the furrow turns. When 

 the furrow is raised into a position almost vertical the 

 dirt falls of its own weight because there is nothing to 

 prevent its downward motion. As the earth begins to 

 fall it naturally crumbles, filling the lower portion of the 

 furrow with loose pulverized soil. The advancing mould- 

 board finishes the work by turning the rest of the 

 furrow on top. 



This process of plowing is exceptionally good for 

 sandy soils because it insures a thorough circulation of 

 air in all parts of the furrow slice. Another advantage 

 of the sloping landside is that the shin acts upon the 

 earth very much in the same manner as a knife 

 acts upon a piece of wood when operated with 



