378 THE COLLIERY GUARDIAN. August 14 1914 The State Mines at Wonthaggi, Victoria. METHODS OF WORKING. By M. BRODIE and P. T. MILLIGAN.* At Wonthaggi, Victoria, Australia, the State Govern- ment owns and operates extensive coal mines, which are under the direct management of the Railways Com- mission in that State. These mines were opened in 1909, and now rank third among Australian producers of coal. The State coal property covers an area of 5,100 acres. About one-half of this has been very thoroughly pros- pected with test drills, and has been shown to bear coal ranging from 2J ft. to 6 ft. in thickness. The drills employed for this prospecting work were of the diamond core drill pattern, owned by the Victoria State Govern- ment, one of them being a class “ H ” 1,000 ft. Sullivan hydraulic cylinder machine. Since the beginning of this work nearly 400 boreholes have been put down. Dur- ing the two years ending June 30, 1913, 27,500 ft. of ------MW salapt---------- Plan ano Longitudinal secr/o/v AA SheiMng /neModofii/orAingAy00L/&LG STALL sysfesn [Coer/} * \ ; a IlflU -----------------m s&urr-------------- Plan ano Longhwnnal SactjonOA SheuMOff/mAaefa/uw/t/^ Ay LO/VQ/MU s//s/M7 ———— Figs. 1 and 2. 9 «■ cl'? = core borings were performed in 104 boreholes, with an average depth of 264 ft. The boring done during the last year proved that a lower seam of coal of workable thick- ness underlies a considerable area of ground north of the present workings. This discovery has increased the estimate of the quantity of coal, 30 in. thick and over, in the mine area, by some 1,500,000 tons, making a total estimated quantity in the area of 28,000,000 tons. Allowing 20 per cent, for loss in working, and deduct- ing 1,434,000 tons already extracted, the total still avail- able for production is about 21,000,000 tons. The core borings are being continued to prove the remainder of the ground. The report of George H. Broome, general manager at * Mine and Quarry. Wonthaggi, for the year ending June 30, 1913, has recently been received. The balance-sheet shows a net surplus profit for the year of about $207,000. The present workings cover an area of about 650 acres, developed by 12 shafts, all of which work the originally discovered or upper seam, which is about 235 ft. from the surface. The coal varies from 2| ft. to 6 ft. in thickness and is very irregular, the entire area being badly broken up by faults. The roof ranges from sand- stone to soft shale, and even to material much broken and as soft as mud. The changes occur very sharply, making the problem of mining and of sustaining the roof a very difficult one. The output of the mines is hoisted from three shafts, Nos. 5, 9, and 10. There is but one tipple and coal handling plant, namely, the one at No. 5, which was enlarged during the past year to handle the entire output of the three mines. The coal from shafts Nos. 9 and 10, some 450 ft. distant, is conveyed above ground to this point by means of an electrically-driven endless rope. The gross tonnage for the year was 462,558 tons. Of this amount, 258,249 tons were screened, 9,239 tons unscreened, and 190,163 tons slack coal — a total of 457,651 tons shipped—of which all but 17,000 tons of screened coal was furnished to the State Government railway. 10,600 tons were furnished to various public departments, and 171,000 tons of slack coal only were disposed of to the public. The average number of employees during the year was 939, comprising 468 coal miners, 250 other miscellaneous underground employees, and 221 surface men. The mine worked 260 days during the year, on a basis of two shifts. The average earnings of the miners were $3*23 per day, after deducting the cost of explosives and light. There was but one fatal accident during the year, this being due to a fall of coal at the working face. Underground miners are paid chiefly on a tonnage basis. Figs. 1 and 2 indicate two typical methods of mining at Wonthaggi, although, as stated above, the great irregularity of the seam makes it difficult to adhere to a given system, as the work progresses from one part of the mine area to another. The sketches show the char- acteristic methods of working at Nos. 9 and 10 shafts. At present these two shafts are producing about one-half the output of the mine, and practically the whole of this coal is being mined by coal-cutting machines of the Sullivan electric room-and-pillar and long-wall patterns. The upper sketch shows the method of working in No. 9 shaft, where the coal is about 6^ ft. high, with a 22 in. dirt band, 18 in. from the floor. As indicated, the method of working is by “ double stall,” with stalls or rooms 42 ft. wide, and two gates, with a track in each. The coal is first mined with a Sullivan room-and-pillar machine on the top of the dirt band, the depth of under- cut being 6 ft. The upper 5 ft. of coal is then shot down and filled away or loaded. The dirt band is next lifted and thrown back into the gob; and lastly, the lower 18 in. of coal is raised and loaded out. In No. 10 shaft working, where the coal is much lower, averaging about 3 ft. 9 in. in thickness, the long- wall method is in vogue. A gate or entrance 7 ft. wide is provided every 33 ft. for handling the machine and loading out the coal, the space between being filled with pack to support the roof. A new opening or slope, known as the McBride Tunnel, is being driven at a gradient of one in 5J, for the development of the area lying to the north of the present workings. It is now several hundred feet in from the entrance, and its object is to cut four succes- sive downthrow faults in the present known seam. This will enable the coal to be extracted from four different levels in about three-quarters of a mile of tunnelling. The objective point of the tunnel is the lower seam of coal mentioned above, in the northern portion of the area. The mines are equipped with the most up-to-date machinery, on the surface as well as underground. The total value of the plant is nearly $1,000,000. Electric winders are employed to raise the coal at the three pre- sent working shafts. Electric power is generated from a central station, which includes a battery of eight boilers fitted with underfeed stokers for burning slack, two generating sets driven by reciprocating engines, and a horizontal turbo-alternator. Current is generated at 5,200 volts. The electric power is distributed from this plant to the different mines, where transformers and rotary converters are located for operating the coal- handling machinery, screens, hoists, tipples, etc. At the Nos. 9 and 10 shafts a change house and bath- rooms were provided for the workmen during the past year. . The building is of wood and corrugated iron con- struction, with a concrete floor, and accommodates 400 men. Forty shower-baths are provided, with an ample supply of hot and cold water. The workmen’s clothes are dried by steam heat. They are attached to hooks, which are handled by chains passing over pulleys on the rafters, so that thev may be raised into position for drying. Mr. Broome’s report stated, in regard to the Sullivan coal cutters :—“ These machines are working very satis- factorily on the long-wall faces, where the coal is from 2 ft. 6 in. to 3 ft. in thickness. Under these conditions they are effecting a saving in cost of about Is. per ton, compared with hand mining, and in addition to this saving recent tests have shown a reduction of 10 per cent, in slack from the machine faces, which at the present selling price means an increase of over 5d. per ton in the value of the product.” During that year three machines were in use. During the 5rear ended June 30, 1913, 11 Sullivan machines were in operation, and the 1913 report states :—‘‘ The larger use of these machines has tended to reduce operating costs, and to improve the product by reducing the percentage of slack. ” In all, the Wonthaggi mine now owns about 25 Sullivan continuous coal cutters, of which 17 are of the long-wall pattern. The 1913 report shows that these State-owned mines are hoisting 2,200 tons per day of two shifts. OBITUARY. The death occurred at Greystoke Castle, near Penrith, last week, of Mr. Henry Charles Howard, chairman of the Cumberland County Council. He was for some years independent chairman of the Cumberland Coal Conciliation Board, and for many years chairman of the Cockermouth, Keswick, and Penrith Railway Company. Mr. Howard might truly be said to have been the leading influence in local self-government in Cumberland. Mr. Howard served the office of High Sheriff for Cumberland in 1879. Deceased was 63 years of age. The death is announced of Mr. George Hall, a coal merchant, of Newcastle. Mr. William Kirton, of Walbottle, has passed away, after a lingering illness, at his residence, Dene Terrace, at the age of 73 years. The deceased gentleman half a century ago went as manager to Walbottle Colliery Brick Works, then carried on by the late Mr. R. O. Lamb, of Axwell, and when that gentleman closed down Lemington Percy Pit and the brick works Mr. Kirton became manager of the brick works at Eltringham, near Prudhoe. After nine months at Eltringham he returned to Walbottle, and re-opened the colliery and brick works in company with his brothers and a Mr. Tarelli, of Newcastle. A few years later the partners sold the colliery and brick making plant to the late Mr. Michael and Mr. Tom Dodd, and commenced as sand quarry owners at the well-known Sand Hill Quarry, New- burn, and at Haydon Bridge Whinstone Quarry. He leaves a widow and married daughter.