Nitro Glycerine As Used For Blasting . - This powerful explosive agent has been used for some days in blasting out the rock at the foot of West First street, where Carrington's Dry Dock is to be located. At noon to-day, we had the pleasure of witnessing the action and power of this compound as applied to this purpose. There were present, Mr. J.G.K. Truair, of the Syracuse Journal, Mr. Park Wheeler, of Syracuse, and numerous other gentlemen, the experiments being conducted by Messrs. White and Harwood, of Syracuse.
Nitro Glycerine is a greasy looking fluid, composed of glycerine, nitric acid, and sulfuric acid, combined in certain proportions. For the purpose of blasting it is much safer to use than powder. A spark will not cause it to explode, and when ignited in an unconfined state, it burns like common oil. To produce an explosion it is necessary that it be confined, and in that state it explodes by concussion.
The method of using it is as follows: Several holes are drilled across the rock, in a line, to the requisite depth. A small quantity of water-lime is then put in and beaten down, to secure dryness, and upon this is poured a half a pound of the glycerine, which is tamped, and another half pound poured in on top. A common safety fuse is used to ignite the charge. The explosive force is exerted equally in all directions, downward, upward and laterally, and is rated at thirteen times that of powder. Its cost is about fourteen shillings per pound, and one pound of glycerine will do the work of from thirteen to sixteen pounds of powder, so that it is much cheaper as well as more safe.
In the case in which we witnessed its operation to-day, the holes in the rock were drilled to a depth of five to ten feet, and about seven feet apart, for a distance of fifty feet across the rock. The blasts broke up the rock for a distance of sixteen feet back from the drill holes, and the execution done by this powerful, and yet harmless looking agent, was perfectly wonderful. The rock was torn in all directions, and wherever there was natural seams it was broken in the line of their direction. It seems to us that in view of its cheapness, comparative safety, and wonderful power, it must come into general use for all purposes of heavy blasting, and must ultimately supersede the manifestly less effective agency of powder.