Rensselaer Republican, Volume 17, Number 36, Rensselaer, Jasper County, 14 May 1885 — Water-Blasting. [ARTICLE]

Water-Blasting.

The value of water as an aid to blasting when used in connection with explosives is rapidly becoming recognized in this country, as well as in the large mines and quarries of Europe. Ordinary blasting with gunpowder in coalmining is done by boring a hole in the face of the coal about two inches in diameter and four or five feet deep. Into this is inserted the powder cartridge, together with the slow fuse, when the hole has been well tamped, filled with any diy refuse rammed in tight, then fired by lighting the fuse. In this operation (and we have described it thus not to show any new ideas connected with it, but for comparison) a very dangerous flame, especially in gaseous pits, is created, and appalling results of ten ensue; carbonic. acid and sulphurous acid gases are generated, very dangerous to miners and mining properties. When it is desired to blast with water together with gunpowder, the process is conducted by inserting into the bore-hole a powder cartridge with the fuse attached as in the ordinary way; next to the powder cartridge is inserted into the bore-hole a tube containing water. These tubes must be as large as the bore-hole will admit, and of any length convenient to handle, the larger the better; they may be made of any cheap material convenient, cheap thin tin-plate, or stout broken paper turned around on a wooden roller, after being well pasted together, the ends closed with corks. The borehole is now tamped in the ordinary manner, the fuse lit, and the cartridge fired in the usual manner. As a result of this process the following points of excellence, among many others, may be briefly mentioned: The powder in exploding bursts the tube containing the water, and, careful estimates show, with increased power or explosive violence, as the rendering force is extended

Through the water in accordance with the well known principles of hydrostatics, practically demonstrated years ago by Bramah, over the enlarged interior area of the bore-hole, due to the space occupied by the water-tube. A much larger quantity of the material to be mined or quarried is thereby brought down or loosened with a small quantity of the explosive used. The heat given off by the burning of the powder and surrounding gases converts a large proportion of the water into steam, the elastic force of which assists in the operation of blasting; the steam and remaining water together extinguish the flame and flash of the powder, and absorb and neutralize the greater portion of the gases and smoke resulting from the explosion. It will readily be seen that by this process are met together economy, power, and safety, the system being simple and effective, and not attended with anything inconsistent with the well-known laws of explosion. It is to be hoped that, in the best interests of humanity, our large and intelligent body of miners and quarrymen will not be slow to adopt an amelioration in the present crude and dangerous process of blasting, wfiich will tend, and, in no small measure, to render premature explosions in mines a thing of the past, rather than one of almost daily occurrence.— Coal Trade Journal.