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a more economical pumping-plant. Some of these companies at the present time are trying to combine to effect this object, asking the Government for a subsidy towards testing the deep ground. In the present state of depression in monetary affairs at the Thames, there is no single company, nor combination of the present companies, that could find the means of procuring a large pumpingplant and sink a shaft to a depth of 2,000 ft., as mentioned by some of the leading mining men as a scheme to be set on foot. Outside capital will have to be procured, and to obtain this sufficient inducement will have to be held out to get people to invest their money in the venture. The ground at the deep levels is practically of no value to the present companies, as they can never work it unless on some large combination scheme, where everyone on the field affected by drainage is interested. The deepest shaft at present on the field where pumping machinery is erected is 640 ft., and at this level, which is about 625 ft. below sea-level, a considerable amount of prospecting has been done, and numerous lodes and leaders cut containing gold. A company was formed in 1884, called the Caledonian Deep-level Prospecting Company, who constructed a drive from the main 640 ft. level, at 275 ft. from the shaft, for a distance of 825 ft., when the drive cut the Moanataiari slide; but the quantity of mullock and water met with at this slide filled the drive for some distance back from the face, where a strong barricade of timber was placed to prevent the mullock from travelling further. In driving this distance seven different lodes and leaders were cut through, varying from 18in. to 4ft. in thickness, all of which were auriferous but not considered rich enough to open out on. At 125 ft. back from the slide a cross-cut was driven in a north-west direction for 500 ft., and in a south-east direction for 800 ft. In the south-east cross-cut a lode 9ft. 6in. in width was cut at 100 ft., another lode lift, thick was cut at 150 ft. The large lodes averaged from 4dwt. to sdwt. of gold per ton. The company afterwards cut another lode and drove on it for 600 ft., which averaged from 12dwt. to 15dwt. of gold per ton. In the north-west cross-cut there were four different lodes cut through which contained gold, antimony, and copper-pyrites. These only went from 2dwt. to 3dwt. of gold per ton. A good deal of prospecting was done by the Deep-level Cross Company, and by the County Council, in a northerly direction from the bottom of the pump-shaft, and several lodes containing refractory ore were cut through ; but at that time this class of ore was looked on as valueless, and consequently was never tested to ascertain its value. The Caledonian Deep-level Prospecting Company arranged to pay the proprietors of the ground 10 per cent, of the gross yield of gold below a certain level. On account of the heavy rate they had to pay for drainage, and not finding any very rich ore, they gave the tribute up, and the water was then allowed to rise in the pump-shaft to the 400 ft. level. Some two years ago the Saxon company, in order to work below this level, agreed to pay an extra drainage-rate if the water was kept down to the 500 ft. level. This rate, £97 10s. per month, was paid by this company for two years and four months, until recently, when they abandoned the lower levels, and the water is now allowed to rise to the 400 ft. level again in the pump-shaft. Very rich stone was got in the New Prince Imperial and Deep-level Cross Companies' Mines, from the 300 ft. level downwards, but it cut out as the lode went down. The same thing takes place in every lode. The gold in the lodes, especially in New Zealand, is always found in shots and ledges with the lodes cutting entirely out and making again. There is ample proof that large lodes exist at the 640 ft. level, and that all those cut through carry less or more gold. No doubt, if these lodes were driven on for some distance, rich deposits of gold would be found in some of them. Although the Big Pump shaft is the deepest where pumping machinery is erected, there is a shaft on the Queen of Beauty Mine which is about 730 ft. in depth; but no work has been done in this mine for about five years. A bottom level was constructed which cut the lode, where some rich specimen-stone is said to have been obtained; but the influx of water on cutting the lode was such that the pumps, which had a 6ft. stroke, making eleven and twelve strokes per minute, could not contend with it. This strain broke the engine-shaft, and work was suspended, the company going into liquidation. They had two sets of 12in. pumps, but this was not sufficient to contend with the water at this depth. The shaft is still intact, and may be useful in the future when the deep levels come to be tested —as ail those engaged in mining at the Thames point out this ground as the best site for sinking a shaft to test the deep levels, the strike of the lodes all tending in this direction. The greatest difficulty in sinking a shaft on this field is the large volume of water to be contended with. The present drainage-pump is 24in. in diameter, worked by a directacting Bull engine, having an Bft. stroke. The manager, who is also the engineer, of this plant informed me that it requires five and a half strokes per minute to keep down the water at the 500 ft. level; and he is under the impression that it would take six and a half strokes per minute to keep down the water at the 640 ft. level, while it only takes about three strokes to keep the water down at the 400 ft. level. At the time the Queen of Beauty pump was at work a large portion of the field was drained by the Big Pump, and consequently there would not be so much water in the ground for the Queen of Beauty pump to lift as there would be if the Big Pump was stopped entirely. Any new pumping-plant would have to be of such dimensions and power as to be able to cope with the whole of the w 7 ater. In making a comparative analysis of the quantity of water lifted by the Big Pump, working six and a half strokes per minute, and the Queen of Beauty pump, working twelve strokes per minute, tlie water lifted by the Big Pump, allowing a loss of 3in. in depth of column at each stroke, would be 948 gallons of water per minute ; while the Queen of Beauty pumps —namely, two 12in. in diameter, with a 6ft. stroke, and working twelve strokes per minute—taking the loss on the same basis as the other, would only lift 646 gallons of water per minute. The travel of the plungers in both the Big Pump, working six and a half strokes per minute, and the Queen of Beauty pump, working twelve strokes, are both in excess of the economical travel of the plunger of a pump, which should not exceed 90ft. per minute — the travel in case of the Big Pump being 104 ft., and in the Queen of Beauty 144 ft., per minute. Seeing, therefore, the speed the latter pump was worked at, the sudden breakage is easily accounted for. It may be safely assumed that, if a new shaft, or the present Queen of Beauty shaft, be sunk to test the deep levels, it will require a pump capable of lifting more water than the Big Pump did