Table of Charges for Ditch Blasting 



Blasting Ditches Without a Blasting Machine 



There are occasions when a ditch has to be cut through very swampy 

 and untrafficable muck, which makes it very difficult for the blaster to 

 conveniently carry out all the work necessary when the blasting machine 

 has to be used. Then again in the same soil it may be imperative to cut 

 a ditch 300 to 500 feet in length in one blast, which cannot be done by 

 means of a blasting machine, as a blasting machine will fire from 30 to 

 250 feet at one time according to its size. When this occurs the follow- 

 ing method should be adopted : 



Punch or bore a row of holes vertically along the center line of the 

 proposed ditch with a bar not less than 1 y 2 inches in diameter, down to a 

 depth approximately within 6 inches of the desired depth of the ditch, 

 spacing them from 18 to 24 inches apart. Each hole should be charged, 

 as soon as made, with one or more cartridges of Du Pont N. G. 60% 

 Dynamite according to depth, as soon as bored. Place in the center hole 

 one extra cartridge primed with a blasting cap carefully crimped to the 

 proper length of waterproof fuse. No tamping is needed provided mud 

 or water covers the charge. The primed cartridge should not be loaded 

 until everybody except the blaster has retired to a considerable distance 

 from the line of the ditch in order to avoid the great amount of dirt 

 thrown out around that vicinity. The primer fuse should be lighted just 

 as soon as possible after the primer is loaded, the blaster, of course, 

 retiring to a safe distance. The charge in the middle hole explodes those 

 in the holes on either side, and the effect of these two is carried to the 

 next and so on almost instantaneously to the ends of the ditch. 



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