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Congress street, Boston) in paper cartridges of various sizes, 

 at the rate of 50 cents for lots under 50 pounds. It is fired 

 with a powerful cap, which cost two cents each. The mate- 

 rial is generally used by tearing open the cartridge and tak- 

 ing as needed. As will bo seen, it is over twice as costly 

 as comtnou blasting powder, but, as every fanner knows, 

 the great cost in blasting is the drilliug, and this is where 

 the saving comes, as it will do as much execution as gunpow- 

 der in a hole of one-third the capacity. Again, it can be 

 loaded far more readily ; push it down hard with a stick, and 

 inserting the cap, fill up with any coarse soil at hand, giving 

 it one or two sharp pushes down with the same stick, put a 

 few handfuls of earth above and an3^ forty or fifty pound rock 

 at hand on that. After, on firing, stand a good distance from 

 the hole, as the rocks fly more than with common poAvder. 

 There is capacity in this explosive which is .wanting in gun- 

 powder ; that of blasting a rock by putting it on the sur- 

 face, when an}^ appearance of a seam can be detected. I 

 have had boulders weighing ten tons, and very solid and hard 

 ones too, knocked all to pieces without any hole having been 

 drilled in them, the first attack being made in a small crevice, 

 just large enough to receive a quarter of a pound of rend- 

 I'ock, which was plastered in there by hand, just like so much 

 mortar. This "strained" an opening into the rock, and two 

 more blasts finished the monster, reducing him into pieces so 

 small that a single horse could handle the largest one. The 

 capacity of smashing into smaller pieces, I find one of the 

 good traits of rendrock. The extra power becomes of value 

 in enabling one to do in a single blast what gunpowder 

 would require two to accomplish. I had two such instances 

 this morning, where fragments of two very large boulders 

 were left in their respective holes that were too near the sur- 

 face and needed removal ; cartridges of rendrock thrust be- 

 tween them did the work capitally, when there was not work- 

 ing surface sufficient for powder to have done any work. As 

 to any extra danger from this compound, there is none to any 



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