Coal Seams near Stony Creek. 29 



of Harpur's Hill, the dip of the beds is reversed, and falls in 

 that direction towards Black Creek, similar phenomena 

 exhibiting themselves in the structure and texture of the 

 deposits, in the association of Palaeozoic fossils with silicified 

 wood, patches of coal, detritus of granite, porphyry, lydian- 

 stone, &c, on the surface, which have been derived from the 

 disintegration of out-cropping fossiliferous conglomerates 

 and sandstones, the latter of which are partly a peperino or 

 " ash." In the railway cuttings, the trap is seen to have 

 been partially contemporaneous with the sedimentary 

 deposits, and partially of later date, as is the case in the 

 Illawarra District. At the axis of the anticlinal, the trap 

 is found in rounded boulders on the edges of the outburst, 

 in the midst of the fossiliferous rocks. 



The diagram (No. 1) represents a section on the 

 north side of Harpur's Hill. No. 2 gives the horizontal 

 section from Maitland to Anvil Creek, in which the coal- 

 seams of Stony Creek, and of the falls to Black Creek, are 

 shown in reverse order, proving that they really belong to 

 the succession of the beds in which they occur. The Trap 

 which thus forms an anticlinal is a spur belonging to 

 Duguid's Hill, a little to the southward of Harpur's Hill, 

 and it breaks out in that direction at the head of Black 

 Creek, and is probably the cause of the divergent drainages 

 from the great bend of the Hunter to the parallel of 33° S. 



By reference to Mitchell's map of the colony in 1854, the 

 state of the case will be understood. .The Myall Bange 

 along the 33rd parallel, and the country north of it to the 

 Hunter, including Ellalong and Tomulpin Hill, and some 

 part of Wallis Creek up to Maitland, consists of the Palae- 

 ozoic fossiliferous formation. The Sugar Loaf and Buttai 

 Ranges, with the mountainous ground to the south of the 

 Myall, including the ranges to Broken Back, consist of beds 

 above that formation. 



On Mulberring Creek, over the fossiliferous beds, coal 

 occurs ; in the Buttai Range the sandstones, &c, .abound 

 with glossopteris and other plants. The Watagon and 

 Broken Back country consists of Hawkesbury rocks, and the 

 summit of Warrawolong is of trap, resting on the latter.* 



On the north side of the Hunter, the Palaeozoic fossiliferous 

 rocks rest on porphyry, which exhibits itself in massive 



* I was upon it in 1843, but then had no barometer with me. It is not 

 lower than 2,000 Ft. 



