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" The place where Mr. Walker desires to prospect is in the No. 1 seam, 150 ft. to the south of a point in the adit 900 ft. in from the mine mouth. The bottom part of the seam is there about a foot in thickness, though further back it was thinner, so it is tending to increase, while the upper part for some distance has been thinning, and I measured it as 6in. in thickness. To determine whether it was desirable to prospect further it was necessary that examinations of the coalfield should be made beyond the boundaries of the leasehold, and such I accordingly carried out. " Geology. " The dividing-range between Golden Bay and the West Coast runs in a north-east and southwest direction, rising somewhat abruptly from the flat land of the Aorere Eiver to a height of 2,000 ft. The first 800 ft. or 900 ft. of the ascent is composed of slates, older limestone, and schist; then there is the usual breccia and heavy conglomerates of the coal-formation of New Zealand, passing upward into finer conglomerate and sandy shales, immediately succeeded by numerous coalseams, with which are interbedded mudstones and shales. Similar rocks, with occasional beds of sandstone, are met in following the sequence upward in Mine Creek to the top of the watershed, 1,940 ft. in height. Possibly twenty outcrops of coal-seams were passed, ranging from a few inches to 15in. in thickness. These dip gently to north-west, and appear to pass conformably under the pitchcoal measures of West Wanganui. Hence it is clear the best way of working these seams would be to tap them from the base of the western scarps, with the drainage free and the dip in favour of the haulage, but transport from the West Coast precludes this at present. " To the immediate north of the mine coal-seams are known to exist, but not being favourably spoken of, and the northern mine-workings not having been found profitable, it was not necessary to make any examination in that direction. Further north the coal-seams are again worked at Pakawau, and there the measures dip to the south. Still further north the general geological structure is an anticline from sea to sea, in place of the abrupt rise and general north-west dip of Ferntown. " Crossing from Pakawau to West Wanganui the upper strata are passed through, including beds of greensand, which, in my opinion, mark the transition conformably to the upper or pitchcoal series. At the northern end of the Inlet, conglomerates, sandstones, and shales, showing local unconformity and strong-current bedding, are exposed. Across the neck of the headland the rocks are obscured by surface-deposits, but reappear on the coast-line, where cliffs of conglomerate, with interstratified soft sandstones hundreds of feet in height, face the Tasman Sea. The Westport coal-measures are said to occur from here northwards, but of these there did not appear to me to be any evidence, and as that position would place them higher in the sequence, it will be preferable for the present to regard them as the time-equivalents of the bituminous coals of Ferntown. " To the south of the mine, where it is proposed to drive, it was desirable to observe the outcrops at as near a point ahead of the workings as possible. With that object in view an ascent of the first large creek on Mr Curtis's land was made, but inaccessible cliffs of the blue older limestone prevented the rocks of the coal-formation being reached. An ascent of a spur some three miles up the valley shows conglomerates outcropping at a height of 1,600 ft. Descending from this to the creek beyond, in what is known as Kerr's Mathoura Lease, a fine but thin coal-seam occurs at a height of 1,185 ft. This measured 2ft. 4in. thick, with a parting a foot above the floor. A second exposure of it showed 2ft. Bin. of coal. The dip varied both in direction and amount, but may be taken as west-north-west, at 1 in 6 to 1 in 9. " About Bft. below this seam an inferior one about lft. in thickness occurs; beneath this there is about 14ft. of shales and mudstones, with an included band of breccia, to the second good seam. This measures 2ft. 6in. thick, but is tending to be shaly near the roof, and there is a band of stone lin. in thickness in the centre of the seam. The floor is sandy shale, underlaid by the heavy bottom conglomerate. Further up the creek than the first seam, and therefore higher in the sequence, several other coal-seams were seen, at least one of which is a workable one. " Owing to the rough nature of the surface no maps have been made showing the positions of the creeks, but the broad aspect of the case is this: that perhaps, two miles to the south of the mine payable coal-seams exist, if anything, rather better than those worked. " Deductions. "The observations made during my brief examination of the Collingwood coalfield point to relatively transient, but frequently recurring, periods of extensive coal-formation, with shallowwater conditions of deposit,—the seas being fed by sluggish streams, excepting immediately after the first submergence of the ancient land-surface, and again towards the close of the coal period. Hence it may reasonably be inferred that, although troughs and inequalities should be expected, the coal-seams, if driven on after thinning, will again be found to thicken and vice versd. " Eegardingthe direction to drive in, my opinion is that towards the south holds out more hope than to the north. Towards the west or dip, the normal direction in which to expect the seams to thicken, no such occurrence has been noticed in the mine-workings. This, however, should only be looked for towards the centre of the syncline or coalfield, and, as it is shown that the dip is fairly persistent and the measures continuous, if such improvement exists it should be found in the deep ground at West Wanganui. As to the particular seam in which to drive, as things are at present, No. 1 appears to be the most suitable, but one of the bottom seams would have been more convenient although not essential for drainage." West Coast. There is a large field containing bituminous coal on the West Coast, and also considerable areas containing both brown and pitch coah There are, at the present time, three bituminous mines 23-C. 3.