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When the top soil is being worked the doors AA are shown by dotted lines as'closing the sluice-box, and diverting the material to each of the side shoots. When the dredge is put to work on the gravel these doors are moved so as to close off the side shoots and open the sluice-box. The side or soil shoots are preferably lined with flat plates, and, when the gravel is being treated, serve as platforms for the man attending to the sluice-box. It is recognised that, in addition to the great advantage of replacing the soil on the tailings, the treatment of the wash by itself—instead of being intermixed with soil, clay, &c, as is usual—is materially conducive to the saving of gold now lost by the ordinary methods. The Blackwater River Gold-dredging Company (Limited) have adopted a novel method of giving the gravel a shaking in its passage down the screen. Instead of the periphery of the screen being truly circular as is usual, there are four " set-offs " of 4 in. each at regular intervals, the design being to give the gravels four drops of 4 in. each in every revolution, and thus prevent the material which is being screened from sliding down the screen in lumps. The effect would naturally be to assist in the disintegration of gravels which might be held together by any cementing-material. This arrangement is illustrated by accompanying sectional sketch.

ACCIDENTS AND FATALITIES. During the year 1904 there were a total of fifteen fatalities in connection with gold-mining operations as compared with nineteen for the previous year. The whole of them, as well as others which were not fatal but considered at the time to be sufficiently serious to be reported to the Department, have been fully inquired into. . One accident in particular, which was somewhat unique in its character, may be especially referred to. This occurred on the 14th March last, at the Energetic Mine, Eeefton. This mine is worked in conjunction with the Wealth of Nations Mine, but the shaft of the former is sunk to a greater depth than the lowest level of the latter. Some four months prior to the accident a winze had been sunk from the Wealth of Nations Mine, and at the time was partially filled with water. A level was driven from the Energetic shaft from a depth lower than the bottom of the winze referred to, and when this had reached a sufficient distance, a rise was put up for the purpose of tapping the water in the winze and subsequently holing through for ventilation. When the machine-drilled borehole designed to let off the water was pricked through by the drill into broken ground at the bottom of the winze, the water came away very gently (the drill being left in the hole), and either gave off, or carried with it, a noxious gas, which suffocated the two men working in the rise and also a third man who was engaged in rescuework. The lights used by the men were not, so far as is known, appreciably affected, but the gas had all the effects on explorers usually experienced by persons inhaling sulphuretted hydrogen, and also blackened metal watch-cases and similar articles. These facts point to the gas liberated being to a great extent, if not entirely, sulphuretted hydrogen, and its presence may probably be accounted for by chemical action resulting from the decomposition of pyrites in the water being at such a stage as to produce the gas. Had the connection been made months before or after, no disastrous results might have occurred, as on the one hand sufficient time would not have elapsed for the necessary chemical changes to have taken place, and on the other hand, time would doubtless have admitted of the completion of the change and of the gases gradually escaping or being neutralised. It is well enough known by seamen that water conveyed in casks or tanks will frequently get so bad as to be unfit for use, but if left alone will come all right again. This is mentioned as a possible parallel to the condition of the water which had accumulated in the winze. It has been a common-enough thing in this and other mining districts to tap water contained in winzes by boreholes from lower levels without any ill effects whatever, and such a practice might be carried out for a century or more without any accident. In my own experience and practice it has been found necessary in several instances to drain very large areas of old workings—in comparison with which the accumulated water in a winze is a mere drop in a bucket —by boring from lower levels, no other means being available, andjthis/too, has been accomplished without the slightest danger of any kind. The accident referred to has caused suggestions to be made for legislative action requiring accumulations of water to be first baled or pumped, and the place where such accumulation existed to be ventilated before being holed into. Eeallylpractical men of experience of course recognise that such suggestions are not applicable in all cases —in fact, it is often absolutely impossible for their being given effect to —and that legislation in the direction indicated would be ineffectual. The Inspectors of Mines have been instructed to draw the attention of mine-owners or managers to the question, and to require, where such a course is reasonably practicable, that places containing accumulations of water shall be baled out and ventilated before other workings are holed into them.