EXPERIMENTS WITH BELLIT IN MINES.

Otago Witness, Issue 1917, 17 August 1888, Page 12

EXPERIMENTS WITH BELLIT IN MINES.

By J. A. Miller.

It may be thought by many that with the invention of gelatine blasting compounds had reached the heigh); of perfection, and that to go beyond it in practical usefulness was impos-sible,-though .equally efficieut material at a considerably reduced price was still " a consummation devoutly to be wished." The latest invention of this kind introduced to the colony is bellit, and it bids fair to fill the bill, and at the same time proves that perfection had not been attained by gelatine. Bellit (pronounce " Bel — leet," with the accent on the second syilable), like dynamite or gelatine, is a compound, and made up into cartridges in the same manner as dynamite. The advantages it has over other blasting compounds are that it can be carried on railways and other conveyances without fear of exploding either by concussion or ignition ; that the fumes following the explosion are not injurious ; that it does not freeze, and therefore requires no thawing, but is always ready for use ; that it is cheaper than either dynamite or gelatine; that it requires no tamping; that it does equally as we'l in wet holes as in dry ones ; and that it is stronger than dynamite. The experiments made with it by me consist — First, of a lifting shot 2ft deep in moderately hard rock in a drive of the ordinary size— viz., 4ft by 6ffc — the result being a thorough shattering of the rock affected by the explosion, and a bruising or crushing up of the rock all round the charge even below the bottom oi the hole. Second, a corner shot, to clear a place for a prop. Here the great crushing power of the bellit showed its advantage over other compounds by pulverising the rock in such a manner that it could be removed easily. For this purpose and for squaring off a face it has no equal* Third, a charge was tried in comparatively soft, dry rock, in which dynamite or gelatine are of but little use. The effect was a very satisfactory shaking of a great mass of the rock. The quantity of bellit at my disposal brought my experiments to an end at this stage, but I feel confident that for general use in mines the compound will be found to have many advantages over those now in use. As to its price and comparative cheapness, it may be mentioned that being about the same price per pound as dynamite, it is nearly half the latter's weight, and as the same quantlty> bulk for bulk, of bellit and dynamite will give equal results^ the former is in effect about half the priSe of the latter. All miners who use blasting compounds should make a trial of bellit, and they will find that by it an advance has been made over other similar compounds. The favourable impressions resulting from my experiments are confirmed by those made by Mr John Eliot, manager of the Premier mine, Macetown, who in addition has experimented with bellit in " uppers," where the difficulties of charging the holes are much increased, snd who found it to act more satisfactorily than , dynamite. It is claimed that beilit can bo exploded by the bellit detonator only. However that may be, these detonators have A decided advantage over otbefr detonators by being bell-mouthec'j giving increased facilities for inserting the fuse} and for preventing the penetration of water between the dap and tho fuse, by the use of either grease or tar.