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C—2

ANNEXURE A. SUMMARY OF REPORTS BY INSPECTORS OF MINES. Nortiihkn Inspection District (Mr. William Bajht.ay, inspector). During 1923 the production of coal from the mines in the Northern District increased hy 113,712 tons. The North Auckland District showed an increase of 36,543 tons, and the Waikato District an increase of 77,169 tons. The total output of both districts for the year is 033,865 tons. Hikurangi District. Hikurangi No. I Colliery. —The south dip reached the boundary during the year, and a commencement was made on the extraction of the available pillars. Owing to the inclination of the seam presenting difficulties in the way of systematic working and trucking of the coal it was decided to enter into a contract with a party of co-operative miners to win the available coal, truck it to the main haulage-road, support the roofs, attend to road-laying details and all other operations in connection with delivery of the output to a point agreed on, excepting only the management and statutory examinations of the mine. During the past six months I have made several inspections of the mine, and I can say that the Act and regulations were strictly observed by both parties, with special consideration to the timbering of the pillar places and the general safety of the men employed. Hikurangi No. 2 Colliery. —Towards the end of the year No. 2 shaft was holed into the connecting level from No. 1 shaft. This shaft is 12 ft. 6 in. in diameter, and is sunk to a depth of 352 ft. complete with a lining of 8 in. of concrete, buntons, and guides for the cages. The development of the mine has been continued during the year by the advance of headings from No. 1 shaft. These headings are moderately inclined, and a number of bords are broken away in anticipation of increasing the output when No. 2 shaft is available for winding coal. The ventilation of No. 1 shaft workings was slightly deficient, due to the contraction of the paturn-air compartment in the shaft, and only thirty-three men were allowed to be ordinarily employed in the ventilating district, in order that that number should receive the amount of air as is pretoribed by the regulations. Two Waddle fans have since been installed, but a larger and more modern fan is required for this colliery. Wilson's Collieries (Wa.ro Mine). —This colliery is under the control of the Wilson's Portland Cement Company (Limited), and the whole of the output of this sub-bituminous coal is utilized in the manufacture of cement at Portland and Warkworth. The abandoned No. 1 section was sealed off with substantial clay stoppings, and mining operations during the year were confined to Nos. 7 and 8 sections, which reached the boundary towards the end of the year, when the pillars were immediately and rapidly attacked in order to win a large proportion of the pillar coal. The district is subject to " creep," and the roadways are liable to become crushed to such an extent as to make the extraction of pillars difficult later on. A stone drive rising 1 in 3 from the fault at No. 6 level intersected a 10 ft. seam of coal at 2\ chains. An auxiliary fan has been installed in the return heading in order to provide ventilation to the development heading. The mine is difficult to ventilate owing to the humidity of the atmosphere acting on the friable roof fireclay, causing it to fall and fill up the return airways, and retarding, by increased friction, the quantity of air. Repair miners are daily employed in the return airways repairing and enlarging the roads. Electricity is used for power-transmission underground, and is conveyed by fully armoured three-core cables. Kerr and Co. (McLeod's Freehold). -This small colliery is worked in two sections. No. 1 section is confined to the extraction of the remaining coal pillars under a number of houses, due care being exercised by the management and owners in seeing that little damage results to the houses through subsidence. No. 2 section is being developed in the bottom seam, which has increased in thickness from 3 ft. to 5 ft., with a stronger roof. Preparations are being made to drain the water from the abandoned West Byron Colliery and open out a section beyond the fault. Silverdale Colliery (Foot and Doel's Crown Lease). —The coal-seam varies from 3 ft. to 6 ft. in thickness, and occurs at shallow depths. Sovoral drives with free outlet for water are driven to win the coal. kSets used systematically to support the roof, and ventilation made easy by short shafts to the surface where required. The output is conveyed by road-wagons to Hikurangi Railway-station. Northern Co-operative Mine (Cunningham's Crown Lease). —A small area of outcrop coal was mined occasionally as trade demanded. Small drives timbered, and regulations observed. Kerr and Wyalt's Mine (Crown, Lease). —The remaining coal pillars were successfully extracted during the first six months of the year. Water proving troublesome, the dip workings were abandoned. Prospecting to win an area of coal which can be obtained by water-free levels. Glen Nell Colliery (Crown Lease). —A party of miners to work on a co-operative basis purchased this Crown lease (part Section 8, Block XVI, Hukerenui Survey District) from. Doel Bros., and proceeded to open out a field of coal. Development consisted of laying 20 chains of tramway to the main road, and a drive several chains in a coal-seam which later proved unprofitable to work. Operations were subsequently suspended at the end of the year. Ferndale Colliery (Cherrie and Go's Crown Lealse). —Mining operations conducted by a party of co-operative miners were successful in winning out small pillars left by a former working. The coal on the outcrop was soft and unsaleable, and prospecting boreholes on the southern part of the lease did not disclose a marketable seam. Foot's Coal-mine (Crown Lease). —During the year Foot Bros, were granted a coal lease over a portion of Crown land formerly worked by the Northern Coal Company. Following the seams from the outcrop an area of unworked coal was discovered of average thickness of 6 ft. Small bords were driven in the seam, enabling a high percentage of pillar coal to be removed in the second working. Thirty chains of inclined tramway connect with the main road, and the output is conveyed by motor-lorry to the Hikurangi Railway-station. Christie's Colliery (Christie's Freehold). —A party of seven co-operative miners work this colliery, with a certificated mine-manager in charge of the operative details of the mine-workings. The headings from the dip have been advanced to the rise through a hard, clean coal area. Boreholes from the surface into the seams are kept in advance of the workings. Timber systematically set to support the roof, and the natural ventilation (by means of shafts) is adequate for present requirements. Rautangata Colliery, Kama. —This small colliery is the property of the Kamo Potteries Company (Limited). Early in the year a drain-level was driven at a low point and drained the water from the old Kamo Mine workings, and a number of standing pillars of coal were subsequently recovered by narrow roadways driven through the old workings. The coal is of a good quality, and the whole of the output is used on the property for briekmaking purposes. Waikato District. Taupiri Extended Colliery, Hvnlly. —During the past year mining operations were confined to Nos. 5 and 7 sections, north side, and Nos. 1 and 6 sections, west side. Tho fault at No. 5 north sectional boundary was pierced by a stone drive which intersected the coal-seam at a lower level. Owing to the creeping movement of the floor at No. 6 north necessitating heavy repairs to the roadways, it was deemed advisable at the end of the year to draw