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country they water to inundations; while the waters that run to the westward spread themselves over extensive marshes in the low grounds of the western interior, from whence they are again conjured up to the higher. regions of the atmosphere by the process of evaporation.
The eastern coast of New Holland, from Bass' Straits to the nineteenth degree of south latitude, presents a range of mountains running parallel to the coast, and consisting, with scarcely any exceptions, of vast conglomerations of sand-stone. There is no granite to be found in masses near the coast for an extent of twelve hundred geographical miles. At the nineteenth parallel of south latitude, however, the country assumes a different appearance ; and a chain of lofty granitic or primitive mountains of various elevation, forms the barrier towards the ocean till the fourteenth parallel of south latitude, or for a distance of three hundred geographical miles. At the latter of these points the sand-stone again resumes its reign, and the land gradually dips till it loses itself in the sea to the northward. From the twenty-fifth degree of south latitude, coral reefs extend along the east coast to Torres' Straits, a narrow passage varying from ten to twenty-five miles in breadth intervening between them and the land. This passage, however, is so intricate, that vessels bound to the northward within the reefs have to cast anchor every night.
They are steered by the eye, and a man is constantly stationed at the topmast-head to give notice of breakers on the coral reefs to the right or left.*
* The following passage illustrative of the geology of the east coat of New Holland in the neigbbourhood of Port Jackson, is extracted from a
The western coasts of all the large divisions of land in the southern hemisphere are remarkably barren and
paper read before the defunct Philosophical Society of New South Wales, by Alexander Berry, Esquire, Member of the Legislative Council of the colony :
“The line of coast presents in general an aspect of bold perpendicular cliffs of sand-stone, lying in horizontal atrata. These cliffs, however, are occasionally interrupted by sandy beaches, behind which the country is low and lat, the bigh land appearing to retire considerably. On a near inspection these spaces now occupied by sandy beaches seem at no very remote period to bave formed the entrance of bays and of arms of the sea. In many places they are even now 80 partially filled up that we still find extensive salt-water lagoons separated from the ocean only by a bank of sand, through which the water yet occasionally forces a passage. The strata of sand-stone consist of beds lying one upon the other in the most regular manner, so that they have evidently never undergone any devia. tion from their original relative situation. It is true that the beds are not invariably strictly borizontal, but this arises perhaps from a gentle yield. ing of the sub-strata. Some of these beds, although perfectly horizontal, and of regular thickness, consist of thin laminæ, which incline at a consider. able angle to the north-east. This sand-stone may generally be called silicious. It is rarely argillaceous ; chiefly in this state over coal : it is then soft and very decomposable. Among the coal measures we occasionally meet thin beds of what may be called calcareous sand-stone.
“The country immediately to the south of Hunter's River is (as is well known) an extensive coal-field. The cliffs on the sea-shore present a most interesting section of the coal-field strata. There, in one day, more information may be obtained than in other places in many years. I traced the strata for nine miles, when they abruptly terminated by suddenly bonding downwards, and sinking below the level of the sea. From this place a long sandy beach and low land extend to the entrance of Lake Macquarie (called also Reid's mistake). The south head of Lake Macquarie rises into bigh cliffs, in which the coal strata again present themselves. Dr. Hutton would have given much for a single day's walk along this shore. Here we see at one glance the progress of some of the most interesting operations of nature—the work of many ages. It appears as if the crust of the earth had been broken, and a bold and regular section forced upwards, and presented to our examination. Between the coal beds we find strata of sand-stone, and beds of slate clay with vege
unpromising in comparison with the eastern. That of New Holland is as sterile and uninviting as it is possible
table impressions ;-sometimes (but more rarely) indurated clay-stone. Embedded in these strata there is found abundance of argillaceous iron ore. This is occasionally cellular and in layers, but for the most part it appears in the form of petrifactions of trees and branches irregularly dispersed. Near the southern termination of the coal-field (that is, where I have mentioned its sinking heneath the level of the sea,) two large beds gradually approachi, and at length meet. They do not however incorporate, but run parallel ; and at this place there is a mass of highly indurated pudding-stone, which reaches from the surface of the coal to the top of the cliff. T'he coal-cliff abruptly terminates at the entrance of Hunter's River, then forming what is called Coal-head. On the north side of the river a sandy beach and low land extend to the vioinity of Port Stephens.
“The coal is decidedly of vegetable origin : the fibre of the wood is often quite distinct.
“ The vegetable impressions in the slate-clay under and over the coal are no less worthy of an attentive consideration. I have seen some of these subterranean plants in full flower, so that a skilful botanist might ascertain even their species. I think that I have been able distinctly to recognise the leaf of the lamia spiralis.
“ I afterwards found by examining the ravines, that the sand-stone strata extended from the sea-coast to the river Nepean on the west. In many of these ravines I found indications of coal, viz. coal-field schistus, with vegetable impressions, argillaceous iron ore, the same calcareous stone formerly indicated, and even fragments of coal. Through that ex. tent of country the sand-stone seems to spread like a level platform ; and although the country rises in hills and ridges, these seem to consist of a mass of clay, the surface of which has been worn into inequalities by the action of water. Consequently the higher portions, which contain most of the original soil, are more fertile than the bottoms of the valleys, unless these have been covered by alluvial depositions. This clay is generally at the surface red, and impregnated with iron : in some places, however, it is white and saponaceous, appearing under the form of beautiful pipe-clay; and I have seen this white clay contain nodules of calcareous stones resembling stalactites, and evidently formed by aqueous deposition. At the depth of a few feet; it generally assumes
for land to be, with the exception perhaps of the vicinity of Swan River. Nothing is visible along the coast but one interminable range of low sand-hills and calcareous rocks: there are no mountains to relieve the eye, and to afford, by the decomposition of their luxuriant vegetation, a rich soil for the valleys: there are no rivers to conduct to the interior : scarcely even a spring of fresh water can be found to recompense the voyager for the trouble of landing. But the west coast of southern Africa, the west coast of South America, and the west coast of New Zealand, are, with few exceptions, equally barren.
In travelling to the westward on the parallel of Port Jackson granite is found in masses at the distance of a hundred miles from the coast, and the country consequently assumes a different and much more interesting appearance. I have already noticed the striking resemblance which the elevated plain of Bathurst exhibits in its general outline to that of a large lake or inland the appearance of schistus, impregnated with sulphate of alumina and sulphate of iron.
Beyond the Nepean River the sand-stone strata are forced upwards, and extend from north to south, forming the range of hills known in the colony by the name of the Blue Mountains. Towards the north, these mountains are sterile and rugged. Towards the south, however, the sand-stone is in many places covered or displaced by whin-stone, which sometimes assumes the form of common, at other times of porphyritic trap. In the latter state it shows itself throughout the verdant, well. watered, and very desirable pastoral district of Argyleshire. In this country, wherever the soil lies upon sand-stone, we find it consisting of the commou Australian clay. Over the whin-stone, again, it invariably consists of light black mould. On advancing further to the south, boths granite and primitive lime-stone are found."
sea. There are indications, however, still less equivocal, of its having at some former period been the place of the rolling of waters. There are various knolls or elevations along its eastern margin, consisting chiefly of innumerable pebbles of quartz, rounded apparently by the action of water in rapid currents or waves.
The high land to the south-westward of Sydney consists of ranges of lime-stone hills, perforated in all directions with extensive subterranean caverns, exactly similar, both in character and stalactitic adornment, to those that are uniformly found in regions of a similar formation both in Europe and America. The limestone formation occurs also to the north-westward of Sydney, at the head of William's River; and a series of the caves I have just mentioned has been recently discovered in the lime-stone cliffs that form the banks of the river Macquarie, at the settlement of Wellington Valley, about two hundred miles to the westward of Sydney. In one of these caves George Ranken, Esq. of Bathurst, discovered a quantity of fossil bones which he entrusted to my care for the Museum of the University of Edinburgh, on my embarking for England in the year 1830. I happened to be the first person in Sydney to whom Mr. R. showed the bones; and perceiving the great importance of the discovery, as it regarded the general interests of science, I endeavoured to direct the attention of the colony to the subject in an anonymous letter, which was published at the time in one of the colonial papers, and which was afterwards republished by Professor Jameson, in the New Edinburgh Philosophical Journal for 1831. The bones were forwarded by Professor Jameson to a