568 president's address. 



Measures; the Hawkesbiuy formation here rests directly upon 

 it. Near Mittagong and Jamberoo the bituminous coal seams 

 have in places been changed into anthracite, owing to the intrusion 

 of igneous rocks which, took place after the deposition of the 

 Wianamatta series, for at Mittagong masses of trachyte have 

 upheaved and penetrated not only the Coal Measures, but also the 

 Hawkesbury and Wianamatta series. Some good sections showing 

 intrusive dykes of trachyte may be seen in the railway cuttings 

 near Mittagong. 



From the Hunter River District the Coal Measures have been 

 traced westerly to Dubbo ; thence they extend in a north-easterly 

 direction, as a belt about 45 miles wide, as far as the Queensland 

 border. A large area of coal bearing strata occurs in the Clarence 

 and Richmond District, but the formation is newer than that of 

 the above-mentioned Coal fields, and as yet no workable coal 

 seams have been found in it. Some time ago Mr. Geological 

 Surveyor, E. F. Pittman, made a report upon some of the coal 

 seams and gold bearing portions of this district"; and at our last 

 monthly meeting, Professor Stephens read an instructive paper, 

 giving a further description of the geology and physical features of 

 the Clarence coal basin, and the eastern slopes of the great 

 Dividing Range. 



Very full information regarding the composition of the New 

 South Wales Coals, with analyses, &c, is given in a report by Mr. 

 W. A. Dixon, F.C.S., F.I.C., and also in the Minerals of New 

 South Wales, by Professor Liversidge, F.R.S., published in the 

 Mineral Products of New South Wales, by the Department of 

 Mines. In the Annual Reports of this Department are published 

 the reports of the Examiner of Coal Fields, Mr. John Mackenzie, 

 F.G.S., giving statistics of the mines, together with diagrammatic 

 sections of the Coal Measures and of the seams worked. 



The Coal measures are estimated to occupy an area of about 

 23,950 square miles. 



There is reason to believe that the coal seams which are now 

 worked in the Northern, Western, and Southern Coal Fields, 

 underlie within a workable depth an area of 3,328 square 



