A FIELD LESSON IN SOILS 



15 



Select the exact spot to be examined and clear the surface 

 of the ground of grass and other vegetation. 



Place the auger over the spot to be examined and give 

 it a few turns, forcing it into the ground four or five inches. 

 Remove the auger with the soil. In 

 pulling the auger a slight backward 

 turn will enable the auger to be pulled 

 with greater ease, and prevent the cav- 

 ing in of the soil around the auger 

 hole. 



Remove the soil from the auger and 

 place it in a pile on the oilcloth provided 

 for the purpose. 



Repeat this operation, forcing the 

 auger down a few inches at a time until 

 the subsurface is reached. This may be 

 determined by the change in color. 



Determine the depth of the surface 

 soil by the distance the auger was sunk 

 into the ground at the time the subsur- 

 face soil was struck. 



Remove a sample of the subsurface 

 soil in the same way that the surface 

 soil was obtained and pile it on the 

 oilcloth by itself. 



Determine the depth of the subsurface soil. 



Remove a sample of the subsoil to a depth of three feet. 

 Place the subsoil in a pile on the oilcloth beside the surface 

 and subsurface soil. 



Examine carefully each layer of soil and record the differ- 



FIG. 1. A soil auger 

 made by welding a 

 f-inch gas pipe to a 

 li-inch wood auger. 



