DYNAMITE IN MINING.

Otago Witness, Issue 1449, 30 August 1879, Page 8

DYNAMITE IN MINING.

The following circular letter has been sent to the inspectors of mines throughout Victoria, by the chief inspector of mines: "In reference to the recent fatal accident which occurred to William Eustace, in the Victoria Beef Gold Mines Olaim at Sandhurst, through the explosion of a charge of dynamite and blasting powder, I beg to inform you that Mr Cosmo Newbury, inspector ef explosives, has reported as follows with reference thereto: — • In my opinion, the danger in using blasting powder with dynamite is that the force exerted by the powder will not in most cases be sufficient to explode the dynamite. It will set fire to it ; but unless j the ground is very strong, it will not explode it. When simply lighted burns slowly, and if the rock gives way owing to the explosion of the powder, the lighted dynamite may be blown away without igniting the whole of the charge, in which case it is likely that some will remain in the bottom of the borehole. This is more likely to oocur when the oharge of dynamite consists of more than one cartridge, or, as is often the case, of broken up cartridges. I don't think that dynamite oa lithofraoteur should ever be fired without the detonator being inserted into the cartridge ; and when a blast leaves a portion of the hole it is good evidence that the dynamite has been burning, has not exploeded, and that a part of the oharge will be found, in the hole. You should caution the mine owners in your district of the danger of using dynamite charges unless they be exploded by means of detonators ; and point out to them that, should any accident hereafter occur from any such practice, they will be held responsible.'"