Page:A sketch of the physical structure of Australia.djvu/39

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27

spar, together with some hard sandstone with quartz pebbles, while some of the low flat islands are made of a soft red sandstone.

West Hill (lat. 21° 50') is composed of basalt: the country around partly of sandstone and partly of clay slate and siliceous slate, with some soft recent sandstone near the beach. Similar rocks were found about the bays north of Cape Palmerston. Cape Hillsborough is composed of a base of igneous rock, capped by a mass of stratified rock, consisting of hard and soft sandstones, dipping S.W. at 15°. In the country at the back of it were small conical hills of columnar basalt. From a small island, a few miles north of Cape Hillsborough, I got a fragment of fossil wood, the only fossil I found on the N.E. coast. The island and apparently the coast behind it consisted of a hard whitish sandstone, weathering- black and red, beds thick and much jointed. Around Whitsunday passage, the rocks were mostly igneous, either an amorphous basalt, a greenstone or a porphyry; others, however, had the appearance of highly altered stratified rocks, with the marks of stratification nearly obliterated. At Cape Upstart we came on true granite very largely developed, to the exclusion of all other rocks whatever.

The rocks mentioned by Leichhardt as found in the interior, between the latitudes of Sandy Cape and Cape Upstart, and at a distance of about 100 or 150 miles from the sea are the following: sand-