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blasting with powder very unsafe in a fiery mine. In last year's report Mr. Cox referred to compressed-lime cartridges, manufactured by Messrs. Sebastian Smith and Moore, as an agent to bring down coal in lieu of explosives. This new agent has been tried at Shipley Collieries, and Mr. Bell, one of Her Majesty's Inspectors of Mines for Great Britain, in an extract from his report published in the Colliery Guardian in August last, says,— The use of compressed-lime cartridges, the invention of Messrs. Smith and Moore, of Shipley Collieries, for the purpose of bringing down coal, in place of gunpowder, has been extensively tried during the past year, and bids fair to become a success. All experiments that I have witnessed have given entire satisfaction, and several of the owners of our fiery mines have laid out their works for its exclusive use. The only difference hitherto experienced is the want of a constant supply of cartridges. The patentees, I believe, have not yet got machinery sufficient at work to supply.the demand. There does not appear to be any more labour in preparing the coal for blowing down for the lime process than is necessary for the use of gunpowder; besides, the lime produces from 10 to 15 per cent, more merchantable round coal, which of itself ought to be an inducement for its general adoption. Then we have the all-important fact that there is no flame given off, and it can be used next to goaves where there is gas without the least danger of explosion. From the account given of this material, and the percentage of round coal it gives above blasting in the ordinary manner with powder, ought in itself to recommend it, especially in some of the mines where there is a large percentage of soft coal. It will be seen from Mr. Binns's report on the workings of the CoalpitHeath and Wallsend Mines at Brunnerton that a deal of gas exists, and that safety-lamps have to be used in the dip-workings of the former mine. This no doubt will add to the cost of getting coal with naked lights, but, under the circumstance that a slight explosion occurred in this mine recently and that a man was slightly burned, the proprietors will no doubt see the necessity of complying with the Inspector's request, until they get their workings better ventilated by artificial means. Quaetz Mines. Quartz-mining is becoming every year of more importance, not only with regard to the number of new mines that are opened up, but the workings are gradually becoming deeper and more intricate, requiring a well-defined method of ventilation, and considerable experience in timbering and filling up the ground as the quartz lodes get worked out. Noxious gases are not so common in quartz workings as they are in the coal measures, yet in some places where the ground is thickly impregnated with iron pyrites their decomposition causes the emission of large quantities of gas from the fissures in the strata; but the system of timbering that is required in main levels, passes, and stopes in order to work the lodes with perfect safety require a considerable amount of skill and careful supervision to see that the work is executed in such a manner as will best secure the safety of the workman and prevent the ground from breaking down. The large quantities of dynamite and lithofracteur used in these mines, and the careless manner in which these explosives are handled by some of the workmen and mine managers, renders it necessary for the provisions of the Regulation of Mines Act to be strictly enforced. The quartz mines in "Westport District are the only mines that have been brought under the Act, and some of the companies felt at first disinclined to comply with the whole of its provisions, inasmuch that it required certain works to be done that they hitherto had not been accustomed to do, and it limited the quantity of explosives that they had been in the habit of taking into the mine. They likewise felt aggrieved that the Act was brought into force in their district only, and this prevented them from readily acquiescing in its introduction. They are, however, now satisfied that the precautions taken are necessary to insure the safe working of the mines and to guard against accidents occurring to any of the workmen. The inspection of these mines has been attended to by Mr. H. A. Gordon, in conjunction with his other duties as Inspecting Engineer of Works on Gold Fields. Statistics. It is satisfactory to find that the coal-mining industry is making rapid and steady progress year by year, and will no doubt continue to do so as the mines get developed, until the production reaches at least the consumption within the