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Ewing's claim, where there is a lacustrine formation about 70ft. in thickness, containing an immense quantity of vertebrae of fishes ; and the great thickness of beds, which can be seen at Muddy Creek, and also at St. Bathan's, containing nothing but the leaves of trees, point out that the climate of that age, which belongs to the older Miocene period, must have been a mild one, in which luxuriant vegetation existed, while intermixed with the quartz-drift are numbers of trees now altered to a semi-lignite condition. The "Old man" bottom overlying this quartz-drift formation to a great depth is itself of a great age, and seems to belong to a more recent period than the quartz drift. While on the subject of the "Maori" or "Old man" bottom: Some of it about Naseby contains a little gold. A place was pointed out to me where a cutting had been made in the " Old man " bottom, and a little gold was obtained therefrom, which bears out my remarks that on the West Coast goldfields this class of material contains gold, and, wherever large streams have denuded a portion of this material, the concentrating action of the stream left the contained gold in these beds. The same thing can be said of some places in the vicinity of Mount Ida, but in a far lesser degree than of the West Coast. The greater portion of the gold found in the alluvial drifts in Otago was derived from a denudation of the quartzose schist rocks, which decomposes very rapidly under atmospheric influences and the action of water. At Kyeburn the same formation is found as at Naseby, and some of the miners are said to be doing fairly well. Messrs. Brown Brothers are constructing a large dam on the land reserved by the Government some years ago from Mr. McCready, and also constructing branch water-races to their main race to supply water to the pipes for the elevating plant. There is a considerable area of auriferous ground in the vicinity of the land reserved by the Government, but it is too deep to work by the ordinary method of sluicing, and Messrs. Brown Brothers are going to work it on the hydraulic elevating system, and in order to do this about 1,400 ft. of rivetted iron pipes have been added to their plant. There is a large stretch of ground between Kyeburn and Naseby on the same line or belt of country as the gold-workings at these two places, and payable gold has been obtained at certain points oh the slope of terraces, but, considering its extent, scarcely any prospecting has been done. None of the ground would pay for working without a supply of water, and the whole of the streams coming out of the main range have long since been taken up, and the water conveyed to work ground at Naseby and other places. There is plenty of ground where men could make fair wages for working here if water was available. Hyde and Hamilton. There has been very little mining carried on at these places for some years ; lately, however, some good prospects have been, got in ground in the vicinity of the Four-mile, at what is known as the Deep Sinking from 120 ft. to 150 ft. in depth. It is said that some of the claims are on a good run of wash-dirt that will give good returns for working; but the cost of sinking will be considerable, as all the timber for the shaft and mining will have to come probably from Southland ; however, sawn timber will not be so expensive, as that can be delivered at Hyde for less than 10s. per 100 ft. It is gratifying to know that the construction of the railway to Hyde has been the means of opening up some ground in the gullies along the line coming from Middlemarch. The workmen in their spare time have been doing some prospecting work, and found ground that will pay them for working, and several claims have been taken up. This shows that, although an old diggings may be left as a place that is worked out, instead of men leaving the district, rushing about on other known fields looking for a new claim, if the same amount of money—and perhaps much less than it cost to move about looking for claims on fresh goldfields—had been spent in prospecting country adjacent to that previously worked, they would have been better off. At Hamilton there is a large area of auriferous ground that would pay very well for working with a good supply of water. Mr. A. McKay, the mining geologist, who was digging on this field in the early days, and who recently made an examination of this part of the colony, states that there are very rich deposits of auriferous quartz-drifts here that could be worked. Hamilton lies in a sort of basin, with the ranges rising to a considerable elevation above it, which are capped in places between Hamilton and Hyde with basaltic rocks, lying sometimes on the schist rocks, sometimes on a white clay, which has quartz wash-drift underlying, which have in places been worked and payable returns of gold obtained. In some places where these have been worked, the wash-drift was followed down until there was too much water to contend with, and consequently the workings were abandoned. There is, however, ample opportunity here for these quartz-drift deposits to be tested under the volcanic sheet, as the water can easily be drained by an adit-level. Mr. McKay, in his report on the geology of Central Otago, states that " on the north side the basin is bounded by a low ridge of slate, to the north of which there is another line of quartz drift. . . . From the lip of the basin to some distance below the schoolhouse the bed of the creek and its banks have been worked for gold. These workings in ordinary mountain creekwash showed the presence of the quartz drifts as a false bottom, and in this rich gold was found and traced to the eastward beyond the immediate banks of the creek. The same line of drift was followed between the outcrop of the slate rock and the cap of volcanic rocks, which to the northwest overlies and obscures these sands. Open workings along this line have been carried to a depth of 40ft. from the surface over a distance of some 300 yards, and from what could be gathered it was the difficulty of contending and dealing with water, not the lack of gold, that prevented the continuance of mining along this line." Mr. McKay states that at the time he was making his recent explorations a miner who had been at Hamilton for many years said that, in the deepest workings referred to, Jdwt. of gold to the tin dish could be obtained at the time that it was abandoned on account of water. 19—C. 3.