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first instance, and the headings are boing pushed ahead to the boundaries. The fireclay roof of the coal-seam has been safely supported with timber systematically spaced and set throughout the roadways. An average output of 20 tons per day is conveyed to the Hikurangi Railway-yards. Northern Go-operative Colliery (Cunningham's Crown Lease). —The available coal on this lease is almost exhausted , and thoro are only a few pillars of inferior coal near the entrance to tho drive remaining for extraction. Surface boreholes put down during the year have not revealed further areas of workable coal. Glen Nell Colliery (Crown Lease). —The seam is only 2 ft. 3 in. in thickness, and occurs at a shallow depth. It is overlain by a stony hard roof, which allords a safe cover for the workmen. Wide places are worked in reduction of the coal pillars, a few remaining for extraction. A new drive is projoeted for winning tho rise coal. Hillside Colliery (Cummings and Party). —A small colliery was opened up by a co-operative party on an isolated portion of the property of the Hikurangi Coal Co., Ltd., under contract and lease from the company. The area was much troubled by faults, and extraction of coal was confined to a rise area in close proximity to tho main-rise heading. Shallow boreholes are being put down by. the party on an adjacent property. The output is carted to Hikurangi Station, a distance of two miles.] Belton's Colliery (Freehold). —The mine is situated on freehold laud adjoining the Hikurangi Valley Road. Operations have been limited to the removal of a strip of coal abandoned by tho Hikurangi Coal Co., Ltd., some years ago. Pour miners have been employed during the year, and generally the mine has been well managed. The party operating the mine pa3 7 s a royalty of 3s. 3d. per ton to the owner of the freehold section, and the output of approximately 20 tons per day has been removed by means of motor-lorries over the Town Hoard's Valley Road to the Hikurangi Railway-yards. The road is in a bad state of repair, and neither the miners nor the owner contributes toward its v pkeep. Ruatangata Colliery (Freehold). —During the year mining operations were suspended for four months pending the settlement of a dispute between the owners and a co-operativo party in respect to the terms and boundaries of tho lease. A Sirocco fan electrically driven has been installed in the return-airway shaft, resulting in a marked improvement of the ventilation of tho mine-workings. A scam of fireclay 4 ft. in thickness has split the seam into two separate seams, 4 ft. and 7 ft. respectively, and it has been found more practicable to work off the top seam before oponing out extensively in the bottom seam. Harrison's Waro Colliery, Whangarei (Freehold). —This colliery was recently acquired by the British Standard Cement Co., Ltd. Boring operations have been conducted on the property in order to prove the oxistenco of tho seam eastward of the existing shafts. The branch railway to the mine, which has not been in use for several years, is being repaired and reconditioned for a train sorvice to the mine. New pumping machinery is being installed underground, and generally the mine-workings are being extended to produco sufficient fuel for tho company's cement-works when they are erected at Whangarei Heads. Ngnngaru Fireclay and Coal Co., Ltd. (Fireclay-mine, Kiripaka). —Tho company exposed an elevated outcrop of fireclay 10 ft. in thickness, intermixed with bands of stone and shale. A loading-bank for motor-lorries has been constructed in close proximity to the main county road within a quarter of a mile of Kiripaka Post-office. Tho fireclay is jigged down a steep surface tramway to the loading-bank. Three largo motor-lorries have been acquired for the purpose of convoying the output to Whangarei Harbour, a distance of ten miles. The clay is then shipped by sea to Auckland. Rotowaro Colliery. —The workings of tho company's three mine sections have been advanced, with encouraging results. In No. 1 mine section the pillars have been withdrawn, within tho limits of the sectional barriers, to the roadways of tho new engine section and the oast section. The main endless haulage-rope has been extended beyond the pillared sections, and two new bord sections have been opened out on the oast side of the mine. Several incipient fires have been detected and suppressed in their early stages, and the affected areas have been isolated by brick stoppings. A workable seam of coal has been proved by No. 3 dip heading to extend towaid the west of the proved troubled area. The available air-current is judiciously divided into four separate splits, thus onsuring a fresh supply of air to each working-section. An additional pumping unit has been installed in order to cope with the increasing inflow of winter months. Tho electric transmission-cables have been carried over tho surface to connect by boreholes at selected points with tho motors and other apparatus underground. Sampling and testing of the mine-dust has been conducted in accordance with the regulations, and the roadways have boen liberally treated with stono-dust, as evidenced by tho whiteness of the walls and by the recorded analyses. In No. 2 mine section the workings are confined to the lower seam. The soam is highly inclined, making the conditions rather difficult for faco-work. Contour headings have been driven to provide access to the rise pillar coal. Marked progress has been made in tho development of No. 3 mine (bottom seam). In addition to winning an output by machine mining, the main headings have advanced 20 chains through a disturbed seam containing numerous faults and drift stone. An extensive area of thick coal has beon proved ahead by boring, and the main headings should soon provide room for tho production of coal on a large scale. Surface developments in progress include the installation of another electrical generating unit, a 500 h.p. steam boiler, and reconditioned mine-workshops affording facilities for conducting all repairs to the plant and machinery. Pukemiro Collieries. —An output of 149,272 tons was obtained from two separate mine sections, named the north and south. In the north mine section the pillars are being successfully removed from throe branch sections. A high percentage of pillar coal is obtained by the method employed to remove the pillars. The roofs of the roadways surrounding the pillars are supported by additional rows of props set to prevent any roof-movement while the successive splits and slices are worked off tho pillars. When the supports are efficient it is often possible to remove entirely all the coal in tho pillar, and in coming back when the props are drawn off—a few at a time —much of the fallen top coal is recovered before the roof stono eventually falls. The driving of headings from the north-west section and from the Glen Afton side of the colliery to connect the brickyard soction is proceeding, both headings being driven through the stone underlying tho seam. In the south mine section the headings and bords of the first working of the seam are approaching the proved faults and boundaries. Tho pillars are intact and should be in a good state of preservation, as they have been enclosed within the rings of stoppings erected to seal off the panels of the first workings. The main south heading is standing on a fault of considerable displacement, and boreholes are being drilled from the surface at intervals to prove the depth of the disturbance of the strata. The roadways in both mines have been liberally treated with incombustible dust. The roadways and mine equipment have been maintained in good condition. The ventilation has been effective and adequate throughout the mine-workings. In the east section the seam was followed to the surface through an intervening gully to a higher outcrop, and preparations arc now being made to grade the roadway for endless-rope haulage. A total of 280 persons was employed in and about the colliery in connection with the operation of the mine. Out of that number coal-miners averaged 110, and tho daily average output of coal per miner was 0-9 tons. Glen Afton Collieries. —This well-established colliery produced an output of 170,254 tons during the year. Headings of considerable length have been driven ahead of bord requirements for the formation of panels and barriers, and mine-dcvelopemnt generally has been maintained in advance of possible output requirements. Eleven mine sections, known locally as A, B, C, D, E, F, Q, H, I, J, and X, have beon opened out, and six of the sections— namely, A, E, F, I, J, and- X—areK —are producing coal in required quantities. Tho other sections have been sealed off by stoppings at the entrances in order to isolate the old workings, and to arrest the loss of carbon by oxidation, which is considerable in mines of variable temperatures. The most important developments comprise the recovery of the seam through the 70 ft. upthrow fault, the formation of -new bord sections beyond the fault-line, and the extension of the subsidiary haulage plant in E section to the inbye connected H section. A section continues to produce a high percentage of pillar coal under excellent pillaring conditions. The main headings in E section have reached the line of the thin coal area which is converging toward the workings of II section. The average temperature of the mine as recorded by hygrometric observations is 64° wet bulb, 66° dry bulb. A