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flows over an alluvial flat to its junction with the lower Moonlight. Healy's Gully owes its modern auriferous deposits probably to the action of the Meg before the stream assumed its present course to join the Moonlight. In the Moonlight Valley the auriferous gravels are mainly derived from the destruction of the surrounding Maitai slates and sandstones. To a small extent gold may have been derived from a development of breccia-conglomerate at the base of the coal-bearing series that, from the northeast, reaches into the bed of the creek opposite the township. The valley of this stream, including also the valleys of some lesser creeks, has been famous for the coarse and nuggety character of the gold found in the alluvial deposits. But in the mode of its occurrence the gold is very patchy, and for long periods the miners work without any return or sufficient reward for their labour. On the whole, however, they are well satisfied with the results, and most of the miners have worked in the near vicinity of where they now are since the first of the rush, or since their arrival at Moonlight. In Garden Gully a great collection of small nuggets and coarse pieces of gold was found at the junction of a small creek coming from the west and joining the main stream near its source. This tributary creek scoured out its upper course and projected the detritus over a precipice, where, over a coal-seam, a waterfall was formed; and, at the foot of the cliff, a shingle-fan, or talus, accumulated.. In this modern deposit—a mixture of gravel, tree-roots, and vegetable mud—a very large quantity of gold was found. This happened some years ago. More recently, a systematic working of the same area has been undertaken, but, up to the present time, without any satisfactory result. Gold-workings are carried on in the valley of Moonlight Creek to and below B.A. Creek; but further down, though there are considerable areas of comparatively promising river-flats, that so far seem to have been very little prospected. Next to Moonlight, following the Grey Valley upwards, is Barker's and Caledonian Creeks. In the first of these the recent alluvial auriferous deposits are derived mainly from high-level terraces and from a development of " Old-man bottom," which from Blackball Creek extends along this side of the Grey Valley as far as the eastern side of Caledonian Creek. The gold-workings in Barker's Creek are not at the present time of great importance. In Caledonian Creek and its tributary, Shellback Creek, a large area of recent alluvium has been turned over, and there is still a considerable population, chiefly Chinamen, engaged in goldmining within the watershed. The gold in the modern wash is partly derived from " Old-man bottom " forming hills in the middle part of the valley, partly from Maitai slates crossing Shellback Creek near its source, and partly from the breccia-conglomerate at the base of the coal-bearing series, which, having a great development farther to the eastward, reaches west, as has been said, into the Moonlight Creek at the township. In Slaty Creek the recent alluvial gold obtained from the bed of the stream has mainly been derived from the conglomerates under the coal, which within this watershed has a very great development. In Black-sand Creek, a tributary branch of Big Biver, the recent alluvia are confined to a narrow and deep valley among mountains of breccia-conglomerate; and, as the creek does not reach through or beyond these breccia-conglomerates, it is evident that the gold in the modern creekwash has its source in these. Beyond the watershed of Slaty or Big Biver the recent alluvial deposits of the Grey Valley and the valley of the Little Grey are not auriferous, or not sufficiently so as to have induced the working of them. The surface-shingle of this part is mainly derived from granite and gneiss forming the greater part of the adjoining Paparoa Bange ; and it is owing, apparently, to the non-auriferous character of these rocks that on this side of the valley no gold-workings extend beyond the valley of Slaty Creek or Big Biver. On the south-east side of the Grey Valley the recent gold-bearing deposits in the valley of Stillwater Creek and Maori Gully are partly derived from " Old-man bottom " or from glacier deposits, of which ample evidence is furnished by the large erratic boulders found in the goldworkings. Over the Arnold Flat, from Lake Brunner to the Grey Biver, there is a broad extent of modern river-shingle, but gold-working over this is confined to a limited distance along the banks of the Arnold. The northern side of the Arnold Flat, towards the No Town Hills, is supposed to be goldbearing in the deep ground, and the several creeks draining from the hills on to the flat, by the denudation of the gravels of the " Old-man bottom " must have carried forward auriferous material now lodged in the beds and lower valleys of those streams, or it carried forward to the north-eastern margin of the Arnold Flat. From the southern slopes of the No Town Hills to the Big Grey the recent alluvial deposits of every stream, large or small, are gold-bearing, and for the most part have been worked, yielding a rich return to the miner. By far the greater amount of such gold has been derived from the gravels of Pliocene date, which are here spoken of as " Old-man bottom." A portion of the gold found on the banks of the Ahaura Biver may, indeed, have been brought from the back-country beyond the area covered by the " Old-man bottom," or washed out of old high-level river-gravels, or directly from auriferous reefs in the schists or unaltered rocks of that part of the district. The amount so carried forward from the back-country can, however, be but small, as the gold-workings along the Ahaura almost cease on passing the south-east boundary of the deposits of " Old-man gravels." The many creeks which owe their gold to deposits of auriferous strata in the Pliocene-gravel formation will be mentioned and described in detail in another part of this report. In the Valley of the Big Grey the gravels of the river-bed and the lower river-flats are at the present time being worked for gold, and would be to a greater extent than they are were it not that there are difficulties in bringing water on to the ground where the richer deposits are known to be. This is due to objections raised by owners of freehold sections to the passing of water-races through their lands. Higher up the river valley—that is, above the junction of the Alexander Biver, and