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without a corresponding washing-table surface, it means that it is lifted in the dredging-buckets, rushed through the sluice-box, and deposited again in the bed of the river, ready to be operated on a second time. This is really what has taken place in regard to some of the dredging operations in the Shotover River. One of the dredges belonging to the Sue Hoy Company have dredged the same ground twice over, and the returns from the second operation were as good as from the first. This in itself is perfectly convincing that the failure attributed to these dredges is due to the loss of goldsaving appliances, and not to the actual dredging operations. In introducing any new system of working, or adopting any entirely new process at first, although it is seen that the general principle involved is correct, yet in very few instances are all the details fully worked out. It is only after considerable experiments have been made on a large scale that the defects can be seen; and the principal defects in dredging-machines at the present day is their gold-saving appliances. In connection with this is a suitable and economical appliance to separate the fine sand from the coarse shingle and stones, for unless this is done it is impossible to save a fair percentage of the fine gold in either the sluice-boxes or tables ; and this applies wherever the gold is in fine dust or in thin minute scaly particles. The film of material operated on ought to be so thin that every grain of sand or gold should roll on the matting or blankets, and not be carried forward with a large body of water; for, although gold has a high specefic gravity, it does not follow that it will sink and remain at the bottom of other materials having a less density. On many occasions gold has been seen actually floating on the surface of the water. The quantity of water required to do the work depends on the pitch or gradient on which the tables are set, and has to be sufficient to keep the surface of the matting or blankets clear of sand. If sand accumulates on the surface of the matting the tables are no longer of any use for gold-saving. In the ordinary dredging-machines "it is a difficult matter to so arrange a. constant discharge from the buckets. Sometimes they come up full and at other times not so; therefore the discharge is somewhat irregular. This affects the quantity of water required for washing purposes. There may be quite sufficient at times, while at other times there will not be enough to carry the sand away so as to leave the surface of the riffles or matting clear; but it is always better to err on the side of having plenty of water than not to have sufficient, as in the one case sand will accumulate on the bottom of the box or table and insure a loss of gold, but in the other case if once the gold got down on the matting the water will seldom lift it again. Although dredging has now been carried on for the last ten years, those interested in it are only beginning to see that something else than lifting a large quantity of material is required to make the dredges deal with the auriferous drifts successfully. Their present defects will, no doubt, in course of time be remedied, and they will eventually be the machines in the future for working the beds of streams and ground of a shallow depth, containing a large quantity of water that cannot be overcome, unless with very heavy and costly pumping machinery. Dredges for working auriferous ground of this description are by far the best machines that have yet been introduced; and, strange although it may appear, it was only when their use was strongly advocated and brought prominently before the public by men who had no experience of gold-working, namely, by Mr. Brooke Smith and Mr. Gibson —the former advocating the Ball dredge and the latter the Welman dredge—■ that they began to come into general use. Both the dredges that were first constructed on the principles advocated were failures, but since then the improvements made in the Welman dredge have made it a useful machine for certain descriptions of ground ; still the bucket-dredge for working the beds of rivers, where there are many stones amongst the wash-drift, is still considered the most suitable. This description of dredge was in work for years before either Mr. Brooke Smith or Mr. Gibson thought of introducing theirs into the colony ; the only difference now being that, instead of the bucket-ladder being on each side of the dredge, as is the case of the one constructed by Kincaid and McQueen and now being used by the Dunedin Company on the Clutha Eiver, the recent dredges are constructed with the bucket-ladder in the centre; still, the centre-bucket dredge, although being superior to the side-bucket dredges, and better for lifting stony wash-drift, is not so suitable as the Welman dredge for lifting the gold from a rocky bottom. A combinationdredge, embracing both principles, would answer better than either of those dredges now in use. The most of the gold will be found lying on the bed-rock and in the crevices where neither of the dredges would ever get; still the Welman dredge will always take more gold off the bottom where the rock is hard than ever can be done by the bucket-dredge. Sue Hoy Company. —This company has four centre-bucket dredges, three of which are on the Big Beach on the Shotover Eiver, and one is at work at Arthur's Point. Only two of the dredges on the Big Beach are being worked ; the first one constructed was found to be too small to dredge deep enough. Several experiments have been made by this company with appliances to separate the coarse gravel, shingle, and stones from the sand. At the time of my visit to the district Mr. Gore, of Dunedin, was constructing a shaking-table on one of the dredges to effect this object. The revolving-screens that they were fitted with at first were not found to work satisfactorily—the revolving motion always caused more sand to be deposited on one side than on the other, consequently on one side the tables worked clear, while on the other the tables were generally filled up with sand, and their use for gold-saving destroyed. However, the returns of gold from these dredges during the last year have been regular, and satisfactory results obtained. Enterprise Company. —This company was formed during the last year, and took over the plant and property of the Horse-shoe Bend Company, who were unsuccessful in carrying on dredging operations, and was wound up. The present company are working the same ground, and although the returns of gold are not large, they are managing to clear expenses. Kawarau Company. —This company have entered into an arrangement with the proprietors of the Golden Link Claim to work their ground, the latter getting the use of the dredge belonging to the Kawarau Company on condition that they receive, or be allowed to retain, 15oz. of gold per week to pay all working expenses and wear and tear, and whatever gold is obtained over and above 15oz. per week is to be equally divided between the two companies. They had just commenced