132 COALFIELDS AND COLLIERIES OF AI T STRALIA. 



In the Southern Coal Field there are two explosive 

 recognised, known as the top and bottom gases. The former 

 is ordinary fire damp. The latter collects in hollows, and can 

 be dammed back like water. Its composition has not yet been 

 properly investigated, but one analysis of a sample taken from 

 the Metropolitan colliery, made by Mr. W. M. Hamlet, returned! 

 8.35 per cent, by volume of CO. 

 14.31 per cent, by volume of COo 

 14.50 per cent, by volume of O. 

 trace per cent, by volume of H. 



7.64 per cent, by volume of CH 4 

 55.20 per cent, by volume of N. 



A map of the Southern Coal Field is given in Fig. 69, 

 which shows the relative positions and areas of the various 

 collieries. 



The Sydney Harbour Colliery. 



This property, comprising an area of 10,167 acres, under- 

 lies the Sydney Harbour, and belongs to an English- Australian 

 Company, known as the Sydney Harbour Collieries Limited. 

 The company holds a concession from the Crown at a low 

 annual rental, which will eventually merge into a royalty of six- 

 pence per ton on large coal, and threepence per ton on small 

 coal. Two boreholes were sunk at Cremorne, on the North Shore 

 side of the harbour. The first, in 1890, reached a total depth 

 of 3005 feet, but struck coal at 2801ft. 9in. ; the second, sunk 

 in 1892, reached a total depth of 2929ft., and struck 10ft. Sin. 

 of good coal at 2917ft. 



A site was secured for the surface works having a water front- 

 age at Long Cove, Balmain, and work commenced eight or nine 

 years ago, under the supervision of Mr. J. L. C. Rae, was con- 

 tinued by Mr. B. Sokehill, and is now under the management 

 of Mr. W. E. Lishman.* The freehold is bounded by two 

 streets and a water frontage of 580ft., and, together with th& 

 land reclaimed from the harbour, has an area of nearly five 

 acres. A sea wall has been built, the finished level of whirh 

 is nine feet above low water. The depth of water off this wall , 

 which is less than a hundred yards from the pit's mouth, is 

 26ft. at low tide. 



*Since the above was written, this colliery has changed 

 hands, and is now under the management of Mr. A. K. Broad- 

 head. 



