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Bathan’s and Hawkdun Mountain, it may be continuous with the Upper Waitaki country. Leaving out of consideration this possible extension of its limits, we find that this great basin has only two outlets for its drainage—one by the gorge of the Taieri River close to the situation of the Highlay diggings, and the other by the gorge of the Molyneux, which commences just below the point where that river receives the Manuherikia. In both these cases it is important to observe that the drainage escapes by a channel which has been, so to speak, cut through the rocky lip of the basin.

Bearing in mind the now well established fact that the original wearing down of the rocky matrix, and the mechanical liberation of its contained gold, has been effected for the most part by long continued wave and current action, either in the sea or in large inland lakes, and that the comparatively feeble and limited action of streams has merely exerted an ever-recurring sifting and sorting influence on the materials thus prepared, we can at once perceive that in this rock-bound basin the conditions have been most favorable for retaining and assorting the debris formed by the degradation of the surrounding schists during the submergence of the land in Tertiary times. The floor of this basin is now occupied by extensive grassy plains, sometimes presenting a wide expanse of many thousand acres in extent, but always terraced and beautifully moulded towards the margin by the action of the retiring waters, as the draining channels were slowly cut by the two rivers before mentioned.

The divide or watershed between these two drainage systems lies between the point of Rough Ridge and Mount Ida, and it is deserving of notice how much more efficiently the larger river, constantly supplied from great natural resources, as lately described by M’Kerrow, has done its work in cutting a drainage channel, than has the small and intermittent Taieri River, for the level to which the plain has in this manner been reduced at where the Molyneux breaks out from it is only 600 feet, while the outlet of the Taieri River is 900 feet above the sea.

Round the margin of the basin, resting on the flanks of the schist ranges, remnants of tertiary strata are to be found to the height of 1000 feet above its lowest present level, or 1600 feet above the sea. Did not this agree well with the thickness of the tertiary strata in other parts of the Province, I might have hesitated to ascribe to river and lake action so extensive degradation even of such incoherent materials, as there must have been removed on an average, several hundred feet of thick... ness from an area of at least 800 square miles.

Within the basin as thus described, from the different class of agencies which have been at work, we have two distinct groups of deposits, which for the present I shall simply designate as the Older Tertiaries and the Never Tertiaries.

The older tertiaries are the deposits which gradually filled up the depression as it passed through the successive stages of submergence, from an estuary-like arm of the sea to a deeply excavated submarine valley. The earliest formed of these strata can only be seen in a few localities where they have been preserved from the succeeding denudition round the margin, and in the deep recesses of the ancient valley. They invariably consist at the base, where they rest on the schist, of strata which indicate the neighbourhood of dry land at the period of their formation, supporting a vigorous vegetation, which has been preserved to us as Brown Coal, associated with finely assorted beds of clay and gravel, indicative of current action in shallow water. Elsewhere in the Province, though not as yet in the district I am treating of, marine shells have been discovered along with these beds.

Over this group have been deposited strata of sand and conglomerate, formed of materials derived from the schistose rocks. The upper portion of this deposit, which is many hundred feet in thickness, consists purely of fragments of quartz, doubtless from the more enduring quality of that substance enabling it better to survive the long-continued attrition. In some cases these upper quartz pebble beds have been firmly cemented by some process not yet clearly understood into a hard resisting rock, which breaks up into huge cubical fragments, that are to be found scattered over slopes from which the underlying and more yielding strata have been removed, or are found capping hills of these strata, which they have preserved such hills are the “White Made Hills” of the gold miner. They are undisturbed outliers of the older tertiaries, and when they rest on a depression in the schistose rocks, and at a considerable altitude, they often prove very rich in gold, having been formed during the period of greater depression, when the current action would manifestly be most intense.

Indications of “Made Hills” were seen throughout the district, and will doubtless be speedily recognised and tested by the practical miner. The more prevalence of blocks of “cement,” as it is technically termed, upon the flanks of a wide valley, forms no sure indication of the presence of a lead, but if the “cement” be found strewn over a limited tract, round which the bed-