7$ THE APPLE 



be squeezed round with index finger and thumb, and then inserted 

 carefully into the detonator, well down to the explosive charge. 

 Do not twist it about. The charge is very sensitive and friction 

 may explode it. Although this operation is not dangerous, yet 

 great care should be exercised. After the fuse is inserted into 

 the detonator as above described, take the cap crimper and crimp 

 the detonator to the fuse. The crimp should be made near the end 

 which the fuse enters, so as not to disturb in any way the explo- 

 sive charge which the blasting cap contains. Do not use common 

 pincers^ knife, or the teeth in this operation. If the work is wet, 

 then smear the joint with tallow, wax, or soap. Do not use oily 

 grease, as the oil might penetrate the fuse wrapping and spoil 

 the powder. 



The next step. The next operation is the insertion of the cap 

 into the dynamite cartridge. This may be done by punching a 

 hole diagonally into the side of the cartridge, inserting the blast- 

 ing cap into it, and tying the fuse to the side of the cartridge with 

 a piece of twine. Electric fusees may be inserted and fastened in 

 the same manner. 



Having primed the cartridge in the manner described, insert it 

 in the borehole on top, or next to the top of the rest of the charge 

 if more than one cartridge is used, and push it carefully home. 

 Putting the explosive into the borehole is called charging or load- 

 ing the borehole. It is generally best in dry ground to slit the 

 paper shells lengthwise in two or three places with a sharp knife 

 before putting the cartridge into the borehole, as a slit cartridge 

 will spread out in the borehole better. The primer should not be 

 slit. Push the cartridges, except the primer cartridge, firmly into 

 place with a wooden stick so that they will expand and fill up their 

 part of the hole, for crevices or air spaces may lessen the power 

 of the explosive. Expanded cartridges also occupy less of the 

 length of the borehole and make possible a heavy charge at the 

 bottom of the hole. The primer is loaded last, or next to the last, 

 and is pushed down only hard enough to touch the preceding 

 cartridge. Each cartridge must touch the one previously loaded, 

 for if there is any space between the cartridge caused by falling 

 dirt or stones, or by the sticking of a cartridge in the borehole, 

 a part of the charge may fail to explode. 



