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nonsense, as they treat no ore there by any other system except smelting. Some years ago the Waihi people sent over a parcel of ore to California, divided into three equal amounts, and distributed them to three different experts for treatment and report. The reports were placed at the disposal of the School of Mines Committee, and showed that no two of the three authorities agreed as to the method of treatment, and none of them returned as large a percentage as the Thames School of Mines. The Waihi people, like the Puhipuhi, deeming that the local talent was beneath their acceptance, also refused to take our advice, and erected expensive and complicated machinery, which they found totally unsuitable, and at last erected the class of machinery that we had at first demonstrated to them was the most suitable. Our experimental plant provided them with a pattern, which they refused to take, but their machinery is now identical with it. The Puhipuhi people have never been quite satisfied with the school of mines in the line of assaying, because we did not give them a high percentage. We also, on every possible occasion, deprecated their running away with the false notion that a laboratory test was a correct guide as to the value of the ore. We pointed out that the way to arrive at this was to take regular samples every half hour of the ore as it passed through the batteries, &c. They appear, however, to stick to the old method of selecting a specimen, assaying it, and computing the value of the whole of the reef by it, and then express surprise that there should be such a difference between the laboratory test and the actual return ; the silver volatilising by roasting, or, rather, drying the ore, is also " buncombe." I understand that one of the methods adopted by these amateurs in arriving at this conclusion was that they took a piece of stone, broke it through the middle, roasted one half, and then assayed it; the other half they assayed going a higher percentage than the half-roasted was put down to volatilisation by heat. Had these amateurs crushed the whole of the stone, and, after thoroughly mixing and dividing it, found a very perceptible difference, there might have been some reason in their conclusion. As it is, their conclusion is perfectly erroneous. We submitted samples of Puhipuhi ore to a white heat in a muffle furnace, and the loss only equalled 3 per cent.; the ore being crushed and passed through a sixty-mesh, left it in the best possible condition for volatilising. You might refer Mr. Thompson to the school of mines report, and also to M. Eissler's ■" Metallurgy of Silver." After his perusal of the latter good practical work, and comparing it with the report, I think he will agree that we put the Puhipuhi people on the right track. I have, &., The Hon. Mr. Seddon, M.H.E., Wellington. Albert Brocb. Approximate Cost of Paper. —Prepai-ation (not given); printing (l,;J0O copies), £1 3s.

Authority : Geobqe Didsbury, Government Printer, Wellington.—lB9l.