87

E.—l

Two seams of coal are at present worked, the sequence of the measures being as follows : — Ft. in. Ft. in. Surface ... Ironstone .. ... ... ... ... ... 1 0 Sandy shale ... ... ... ... ... ... 3 0 Coal" ... ... ... ... ... ... ... 1 0 Sandy shale ... ... ... ... ... ... 2 6 Coal" ... ... ... ... ... ... ... 1 8 Sandy shale ... ... ... ... ... ... 4 0 Coal ... ... ... ... ... ... ... 3 6 16 8 Dip, E. 10° S„ 1 in 3. wdiile about 3 chains to the west a small prospecting drive is being put in, with a view of proving the existence of any lower seams of coal. The workings are in fair order considering the system employed, but repairs to the roadway appear to be much neglected. Timber is too sparingly used, and where used is far too light, the props in most instances being only from 3 inches to 4 inches diameter; and, in all cases where pressure has been put on them, they appear to have given to the weight. No attention is paid to leading the air along the working faces, the greater part of the intake air, for want of stoppings, being taken up the first heading to a small air-shaft near tho mouth of the mine, while the air in the body of the workings, towards the face, is very foul, all but extinguishing tho candle, while the air-course is choked with fallen debris owing to the timbering having given to tho superincumbent pressure; and at the time of Mr. Denniston's visit (19th October, 1877,) Mr. Brown himself, the manager, considered it too unsafe to traverse. When I visited the mine on the Bth June, the ventilation appeared to be somewhat better ; but the faulty timbers have not been replaced, and many of them are so crushed by the creep of the floor as to be entirely useless. Hart's Coal Mine, on the banks of the Selwyn Eiver, and near the Gorge, was formerly wrought by a tunnel, which has now r fallen in. The coal here had been altered, probably by the dolerite flow, and is 2 feet thick. An approximate quantity of 8,000 tons has been obtained from it. At present an incline plane is being driven by a party of working miners, with a view of testing the existence of a lower seam. This has not yet been met with, but very little work had been expended up to the date of Mr. Denniston's visit, and when I visited the place the work was abandoned. St. Andrew's Colliery, Oamaru, is a small colliery on the north side of the " Tables," facing the Waitaki Eiver, and is worked by a tunnel, driven a distance of 885 links through conglomerate, cutting a seam of brown coal 10 feet thick. The following is the sequence of the measures : — Ft. in. Ft. in. Fine quartz conglomerate ... ... ... ... ... 50 0 Micaceous shale and impure fireclay... ... ... ... 25 0 Coal ... ... ... ... ... ... ... 9 0 Shale ... ... ... ... ... ... ... 2 0 Coal ... ... ... ... ... ... ... 10 0 96 0 the lower seam being w rorked and the whole thickness won upon an irregular system of room and ranee. This colliery has been at work, off and on. for nine years, and has from time to time had to be abandoned in consequence of small portions of the workings catching fire, owing to the slack being heaped in the wrought-out area, and igniting spontaneously. When visited, this colliery had just been re-opened, and the general repairs were being attended to, which, so far as proceeded with, appeared to be done in a workmanlike manner. A good current of air is obtained throughout these workings, the intake being led by the tunnel through the workings, at tho extremity of which it is discharged by a small air-shaft. Prince Alfred Colliery (Willett's), Oamaru, is situated about two miles to the eastward of the former. It is worked by an adit drive through conglomerate, similar beds being met with here to what are found at the St. Andrew's Colliery, but here the upper seam is worked, only the lower 6 feet being taken out, the remaining 3 feet being left as a support for the roof, which has been found to be very treacherous, the more so as the levels have been driven 10 feet wide and the stalls 15 feet —far too great a width for the safety of the workings when the character of the roof is considered. Already two falls have resulted from this wide driving, causing a subsidence of the measures, and necessitating a considerable amount of timbering, which has been well put in, and appears to be sufficiently strong to render the workings safe. No system of ventilation exists here at all, as there is no return air-course, and a few hours after commencing to work the mine has to he left, as the air becomes exhausted. Awamoko Colliery, Oamaru, is situated on the banks of the Awamoko Creek, about 10 miles west of the two former collieries. The coal, which is 3 feet thick, is entered upon by a tunnel driven a distance of 2 chains, with one bord broken off and driven only a few feet. The workings are too small at present to merit any special remarks on the system employed, &c. The Real Mackay Mine, Tokomairiro, is situated about 5 miles to the south-east of the Tokomairiro township, and is in the same seam of coal as that worked by the Bruce Coal-Mining Company, the face being about 12 chains south of the company's prospecting drives. The coal here is quarried on a face, and delivered into carts direct, as no underground workings exist, the coal being worked open cast.