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goes down. There is, however, a quantity of stone near the surface which may pay to take out and treat. Some of the ground on the range between the Kuaotunu Township and Waitaia Creek has again been taken up, and some fair samples of stone are being obtained from the claim known as the "Blackjack," but there is very little work being done on this portion of the field. During last year 10,093 tons of stone was crushed, and 2,760 tons of tailings treated, which yielded 8,4830z. 13dwt. and 1,0230z. 4dwt. of gold respectively, representing an aggregate value of about £25,944. The average number of men employed in the claims on wages was 135, and seven men worked as tributers. Taking the average number of men employed in the mines, and the quantity of gold obtained, gives an average of 660z. 15dwt. 2gr. for each man employed on wages; the quantity of gold obtained by tributers, being 6940z. 18dwt., is equal to 990z. sdwt. 10gr. of gold for each man employed on tribute. The area of ground held in many claims at Kuaotunu is about 194 acres 2 roods, and the total number of men employed, including tributers, being 142, shows that there is on the average one man employed to every 1 acre 1 rood 19 perches. Further on in this report will be found some interesting geological notes on the Kuaotunu Mining District by J. Park, Esq., of the Thames School of Mines. Try Fluke Company. —This company has been working continuously since the field was first opened, and the lode still continues to carry gold as it goes down, although not nearly so rich as it was at the surface. This company has recently purchased the Carbine Mine, the price paid for it being £250. The company is working two lodes in the Try Fluke Mine ; one of them is from 18in. to 2ft. in thickness, and. the main Try Fluke reef is from 3ft. to Bft. in thickness. During last year they crushed 4,116 tons of stone at the battery, which yielded 2,1860z. of gold, being an average of about lOdwt. 15gr. of gold per ton. Fifteen hundred and fifty-two tons of tailings have also been treated, which yielded 5500z. of gold, or about 7dwt. 3gr. of gold per ton. In my last report reference was made to the loss of gold by this company, and the amount that was daily being carried away with the water. The company has at last become aware of the fact that some change in the treatment is required ; they accordingly entered into an arrangement with the Cassel Company to erect one of their plants to treat their tailings. At the annual meeting of the company, held on the 31st January last, the chairman of directors stated that the cost of a 30-ton Cassel plant was £640, and for the first five weeks' work gold to the value of £825 was obtained from the tailings. At first when they commenced this process the cost of treatment was about 7s. per ton, but it has now been reduced to about 4s. per ton. The balance-sheet of the company for the year ending the 31st December last showed that 4,910 tons of stone had been crushed, which yielded 2,3770z. 3dwt. of gold, representing a value of £6,123 19s. 3d., and that for the same period the wages, cost of cartage, and everything connected with the mine, amounted to £2,576; the expenses in connection with working the crushing-battery being £1,963. This shows that the cost of mining was 12s. 4d. per ton, and the cost of crushing 9s. 3d. per ton, making a total of £1 Is. 7d., being the total cost of mining and crushing, exclusive of the cost of working the Cassel plant; and during the five weeks the Cassel plant was at work the expenditure for wages and supplies amounted to £202 os. 10d. Adding this to the original cost of the plant—namely, £640, makes a total of £846; whereas the value of the gold obtained was £825, so that the first five weeks' work paid for the cost of the plant, less £21. It is said that 95 per cent, of the gold in the tailings was saved ; this, however, may be taken for what it is worth. Considering the extremely fine gold there is at Kuaotunu, and the coarse sand in the tailings, it is doubtful if so high a percentage could be recovered unless the sand had been repulverised. It may stand in the same category as the assays made at the Te Aroha Syndicate Company's plant at Waiorongomai, where the tailings were assayed before going into-the vats, and also assayed after the cyanide solution had been filtered through, which gave high results by merely taking the percentage of the assay-value; but when the bullion was produced, it was found it came a long way short of the quantity it ought to have been, judging by the assays. When all the circumstances are known, the same thing might apply at Kuaotunu. When the particles of gold are in so finely divided a state as they are in the ore at Kuaotunu, and the sand not finely pulverised, a very high percentage could hardly be expected. Be that as it may, it is certainly a step in the right direction, and, no doubt, many of the other companies will soon follow the mode of treatment adopted by the Try Fluke Company, as the ore on this field is particularly adapted to treatment by the Cassel process. Cassel Plant. —The Cassel plant at the Try Fluke Company's works consists of four working tanks, each 12ft. wide, 16ft. long, and 4ft. deep, having a filter-bed of 3in., covered over with a coarse cloth. The depth of ore in the tanks is about 3ft. 6in., and about six tons of 0-25 per cent. cyanide solution is used. This is what is termed the strong solution. The tap allowing the filtrate to flow away is so regulated as to take about twenty-four hours to filter through this solution, after flowing through six compartments with filter boxes, which are filled with fine zinc-turnings. The solution passes into a sump, 18ft. long by 14ft. wide and 4ft. deep, and from this it is pumped into the tank again, which forms the second solution. The latter solution is allowed to filter through as fast as possible, and, after going through the boxes filled with zinc, it flows into another sump of the same dimensions as those already mentioned. The ore is then washed with pure water, that is, water is allowed to filter through the ore, to wash out any of the cyanide solution remaining in it, after which the material is shovelled out of the tanks and run on to the waste-heap. The second solution in the sump, previously referred to, is pumped up into a reservoir placed at a higher level than the working tanks. This reservoir is 10ft. long, Bft. wide, and sft. deep, the solution being made up to the required strength before again being used. The company tried to run the tailings direct into the tanks from the battery, but they found that the amount of slimes in the ore prevented the cyanide solution from filtering, and they were at the time of my visit making arrangements to allow the tailings to flow into a large pit, from which they would be lifted into the cyanide working tanks. They intended to make experiments with the working of the slimes, so aa to get over the question of filtration. This seems at the present time to be the weak point in