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With very few exceptions, steam-power is used for driving dredging machinery. Electricity is adopted at Miller's Flat and Fourteen-mile Beach (Clutha River), the current in each case being generated by water-power. A large dredge is under construction at Earnscleugh Flat, near Clyde, and will be electrically-driven, the power-station being on the Fraser River. Particulars of this dredge follow, and a drawing is also reproduced. In California several electrically driven dredges have been designed and put to work by Mr. R. H. Postlethwaite, formerly of the New Zealand Engineering and Electrical Company, Dunedin, and now connected with the Risdon Ironworks, San Francisco. Mr. Postlethwaite has very kindly sent me a general drawing of one of these dredges. Whilst the general principles of the New Zealand design are followed, there are several differences in detail. Among these I notice that each department of the dredge's work has a separate motor for driving. A machine having buckets of 5-cubic-feet capacity, constructed to dredge 30 ft. below water-line, and to stack its tailings to a similar height above water, has six motors—viz., one for working each of the following portions of the machinery : (1) Buckets, (2) ladder-winch, (3) line-winches, (4) centrifugal pumps, (5) screen and elevator, (6) centrifugal sand-pump. The last-named appliance is adopted for the purpose of dealing with a portion of the sand and water from the tables, and discharging the same through a pipe (running parallel with the elevator) on to the tailings-heap. At Waipori Mr. W. O'Brien has adopted water-power direct for the purpose of driving a small dredge. In this case a Pelton wheel, from which the machinery is driven, is mounted on the dredge. Water is conveyed under a head of 45 ft. in pipes, but to allow of the movements of the dredge without interfering with the water-supply the pipes between the dredge and the bank are carried on small pontoons, and have ball joints. By this means the varying movements due to height of water and shifting of dredge are met. The disadvantages of the system adopted for conveying the water under pressure to the Pelton wheel appear to be in the wear-and-tear to which these joints will be subjected, and with a greater pressure of water than is available here armoured hose would be found to answer the requirements, and be free from the objections named. The advantages claimed are that engines, boilers, and fuel, with their attendant costs, are dispensed with, and the water used for driving the Pelton wheel or wheels is afterwards utilised for washing the dredged material, thereby obviating the necessity for pumping water for this purpose. As is well known, the power absorbed in this department of gold-dredging work forms a very considerable percentage of the whole. Whilst there may be considerable difficulty in working a dredge in this manner in rapid currents, there may also be many places where water under pressure is available for working dredges on flats or sluggish streams by the system under notice. Where desirable, separate motors could be used for buckets, winches, and elevator. The safety of persons employed on dredges has occupied the attention of the department during the last three years, and the special rules dealing with this aspect of the working-conditions of dredge-mining have been revised, such additions being made thereto as further experience has suggested in the interests of safety to life and limb. It is pleasing to note that in some instances dredgemasters have made the provisions for the safety of their crews a matter of earnest consideration ; but at the same time it is greatly to be regretted that in many instances employes are found to be recklessly careless and foolhardy. The special rules as now amended impose their observance upon employes as well as employers, and where workmen wilfully violate the regulations made for their own safety employers may not only take action in the Courts against them, but it is their duty to do so. The work of running lines between dredges and the banks of swift-flowing rivers is perhaps one of the most dangerous features of a dredgeman's occupation, and experience has repeatedly proved the necessity for the special rule which requires the crews of boats so engaged to wear life-belts during such operations. The capsizing of boats has occurred on several occasions, and lives have been lost. It is with much pleasure that I have to refer to the invention by Mr. T. Shore—dredgemaster of the Alpine Consols dredge, Cromwell Gorge, Otago—of an appliance which has for its object the safety of employes when engaged in running lines. The general method is to coil up the rope in the bottom of the boat, and for one man to pay it out by hand. In such rivers as the Kawarau, Clutha, and similar rapid streams the boat sometimes gets beyond the control of the oarsman to some extent, with the result that the man paying out the rope by hand is thrown overboard by a sudden jerk. To obviate this, Mr. Shore provides a windlass-barrel 9 in. in diameter, fitted at one end with a flange 2 ft. in diameter, and at the other with a hand-wheel of similar size. The whole is mounted on an angle-iron frame-support, which can readily be connected with and removed from the sides of the boat. The flange-wheel is provided with a powerful screw-brake to regulate the speed of boat and consequent paying out of the line, any taking-up of the line being effected by means of the hand-wheel. The rope or line is guided over the bow of the boat by a fair-lead in the shape of a pair or ram's horns, and designed with the object of preventing the rope from being jerked out. The appliance has worked very satisfactorily, and has also caused much interest among dredge-managers. If extensively adopted it may be the means of saving many valuable lives. The invention (which I understand has been patented by Mr. Shore) is very simple, and will be thoroughly understood from the photographs accompanying. In connection with dredging-work, Mr. J. F. Kitto, of Cromwell, has published a very handy manual for dredgemen. As Mr. Kitto is a dredgemaster of many years' responsible and varied experience, he is well qualified to deal with this subject, and describes in plain, simple language what to do, and how to do it. The manual should, and no doubt will, be of great service to young men qualifying for the position of dredgemaster. As regards the extent to which the industry has attained, I am not in a position to give the exact numbers of dredges at the 31st December, 1900, but the following figures, which will not differ to any great extent, are made up to the 31st March, 1901:— 4—C. 3,