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THE FARMERS HANDBOOK. 



used to a iriucli greater extent, and the effect of which is plainly noticeable 

 when grub-hole charges are used, is that of bunching the charge. By this 

 is meant putting tne several plugs that comprise the charge in one lump, 

 instead of, as in a bulb-bar hole, distributing them to a certain extent up the 

 length of the hole. To accomplish this, the hole has to be what is termed 

 " bulled " ; this consists of opening out a chamber at the bottom or deepest 

 point, by exploding a small charge of gelignite at that point before the main 

 charge is put in position. The size of this " bulling " charge depends on the 

 number of plugs it is intended to use in the attack upon the stump itself and 

 the physical condition of the ground. Generally speaking, however, one- 

 third of a plug of gelignite will open up a cavity about 6 inches in diameter 



ground /eve/ 



Fig. 7.—" Bulling " a Hole. 



A small charge of, say, one-third of a plug is first exploded at the bottom of a hole driven with a bai, 



and in the chamber so created ten to fifteen plugs can be placed as the " business charge." 



every way, which will hold anything from ten to fifteen plugs. To prepare 

 this " bulling " charge of a third of a plug and to explode it in the bottom 

 of the hole, take a No. 6 detonator, free from sawdust packing, and insert 

 a piece of ordinary fuse about 8 inches long in the open end and crimp it 

 on in the usual way with pliers ; then, after making a hole with the handle 

 of the pliers or a piece of stick in the piece of a plug, push the detonator 

 with fuse attached into the hole and split the top end of the fuse so as to 

 expose the powder to facilitate lighting. So soon as the fuse is lit and the 

 powder flame spits out, drop the charge quickly into thv bulb-bar hole and 

 push it down to the bottom with the tamping stick, then remove the tamping 

 stick and stand to one side, as the explosion throws out a certain amount of 



