EXPLOSIVES 



189 



stump with strong lateral roots can be taken out with less 

 explosive if a charge is placed immediately under each root 

 and fired simultaneously with a machine (Fig. 170). The 



CLAYTAMPINS 







After E. I. flu Pont de Nemours & Co. 



Fig. 170. Placing the charge in stump with lateral roots 



condition of the soil has considerable bearing on the grade 

 and quantity of explosive to be used and the position of the 

 charge. 



Bowlders. For breaking bowlders three methods are 

 used in the placing of charges. One is known as mud- 

 capping, in which the charge is placed in some depression 

 on top of the bowlder and covered with mud. The second 

 is called snake-holing, in which the charge is placed in a 

 hole bored under the bowlder. In the third method, or 

 block-holing, a hole is drilled into the bowlder and the 

 charge placed near the center. The results obtained from 



