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TASMANIA
, a See also:British colonial See also:state, forming See also:part of the Australian See also:Commonwealth
.
It is composed of the See also:island of Tasmania and its adjoining islands, and is separated from the Australian See also:continent on the See also:south-See also:east by See also:Bass Strait
.
The
See also:Sea See also:Elephant See also:Rook
.See also: Besides the See also:main entrance to Storm Bay, between Cape Raoul and Tasman See also:Head, there is D'See also:Entrecasteaux Channel, which divides See also:North and South See also:Bruni Island from the mainland . This channel has two branches, the easterly forming the entrance into Storm Bay, and the western being the estuary of the Huon See also:river . On the east See also:coast lies the peculiarly-shaped Maria Island, almost severed by deep indentations on the east and See also:west . Above this island is See also:Oyster Bay, formed by the See also:projection, See also:Freycinet Peninsula . On the south are some very prominent headlands . In the south-west lies the See also:fine See also:harbour of See also:Port Davey, which receives several small See also:rivers . Proceeding northward along the west coast the most conspicuous headlands are Rocky Point, Point Ilibbs and Cape Sorell, which stands at the entrance of See also:Macquarie Harbour, the deep inlet receiving the See also:waters of the river See also:Gordon C Wiohham xent'Craup See also:frith 4, Judgement Rim . .See also:Wright Poch B a a s S t r a i t Craggy le 4istare Pipamid . C.Franh/and Pascoe /s..: See also:Marshall See also:Hummock See also:Low Manngege r ./.Vt See also:Group `-- . ` Chappellele., Vanai [See also:tart I . G.wse / BadgerL40 . CaPe ` w e H Cq Clarhe I. lO~r ssager o l.n °o aPS~ °v-t ~tlnha Strait PGLP t e obi o~.o i °~,oe^,v '!° .
. °See also:Swan 1
.
C.Natura/isle
ws^~Oec~o~~q\ 0'9~r
_r_
.
I TJ86a'` , ddustone
See also:Lodi
Swan Port 4. rouruille
s Panynsu/o mp 5?Sohouten l
.
1;9'Toillefen4s, -
labdna
.
.
See also:Mario I
.
Riedle B
.
See also:Mar/on Bay
.Fred' Rendrich Forestieri Peninsula
raeman Peninsula
and several smaller streams
.
North of this there are several prominent headlands
.
The west coast terminates at Cape Grim, opposite which are the group known by the name of See also:Hunter's Islands
.
Going eastward along the north coast Circular Head is met with, a narrow peninsula See also:running out for six See also:miles and terminating in a rocky See also:bluff 400 ft. high
.
Further east are Emu Bay, Port Frederick, Port Sorell and Port Dalrymple, into which flows the Tamar river, on which See also:Launceston is situated
.
In Bass Strait are several large islands belonging to Tasmania; King's, See also:Flinders, Cape Barren
and See also:
Flinders Island has an area 1 to the subsidence of the See also:land, of which the islands in the Bass Strait of 513,000 acres
.
Among the rivers flowing northward to Bass are remnants, which then connected Tasmania with the continent
.
The latest date for the existence of this connexion is given by the See also:absence from Tasmania of the See also:dingo, the See also:lyre-See also:bird and the See also:giant marsupials; so that the See also:isolation of Tasmania was earlier than the arrival of those animals in south-eastern See also:Australia
.
That it was not much earlier is shown by the fact that some still living See also:species of mammals, such as the thylacine, existed before the separation
.
The See also:geological sequence in Tasmania is full, and the island contains a better See also:series of Carboniferous rocks than is found in See also:Victoria
.
The See also:nucleus of the island is a See also:block of Archean rocks, which are not, so far as is known, extensively exposed
.
The most certain representatives of the Archean are the See also:gneiss and See also:schists of the See also:Dove river and the upper Forth, and the See also:hornblende-schists, which are exposed in the river valleys on the margins of the central See also:plateau
.
The See also:Mount See also:Lyell schists which underlie the West Coast Range, and the quartzites of Port Davey on the western coast, ,have also been regarded as Archean
.
The See also:Lower Palaeozoic systems begin with the See also:Cambrian, which are found in See also:northern Tasmania near See also:Latrobe, and contain Cambrian fossils as Dikelocephalus Tasmanicus and Conocephalites stephensi
.
The Ordovician See also:system has not been certainly identified; but probably many of the slates and quartzites ! in north-western Tasmania and of the See also:mining See also: The Devonian system is best represented by the massive conglomerates and quartzites, which See also:form the West Coast Range extending from Mount Lyell on Macquarie Harbour, through Mounts See also:Jukes, See also:Owen, Lyell, See also:Murchison and See also:Geikie, to Mount See also:Black . These mountains consist of detached remnants of a See also:sheet of See also:quartz conglomerates, interbedded with sandstones, containing crinoid stems and obscure brachiopods . They See also:rest unconformably on the Silurian rocks on the King river and to the west are faulted against the schists by a powerful overthrust See also:fault, traversing the Mount Lyell See also:copper field . A northern See also:extension of these conglomerates forms the See also:Dial Range near Burnie . The Devonian See also:period, as in Victoria, was marked by a series of granitic intrusions, which altered the older beds on the contact, while the quartz-See also:porphyry dikes, which are intrusive in the Silurian rocks at the Mount Bischoff tin mine, doubtless belong to this period . The Carboniferous system begins with a series of marine limestones, shales and grits, including a See also:rich Lower Carboniferous fauna . The Carboniferous rocks occupy the whole of the south-eastern corner of Tasmania; and one outlier occurs on the northern coast in the See also:Mersey Valley . This formation See also:helps to build up the central plateau, and a See also:band outcrops around its edge . The Upper Carboniferous includes beds of shale and See also:coal; but though the coal is See also:good, the seams are thin and have not been much worked . The Coal See also:Measures are covered by marine shales with numerous bryozoa; and, on the See also:horizon of the Greta Coal Measures of New South See also:Wales, is a See also:bed of Carboniferous glacial deposits . The Mesozoic system is not well developed . It is usually regarded as beginning with a fresh-See also:water series containing the remains of See also:fish and labyrinthodonts; but as it also contains Vertebraria it is probably Palaeozoic; and this series is covered by sandstones and shales which are probably of Triassic See also:age .
The most conspicuous member of the Mesozoic group is the sheet of See also:diabase and See also:dolerite, made up of laccolites and sills, which covers most of the central plateau of Tasmania
.
These rocks form the prominent scarps, known as the Tiers, on the edge of the plateau, and its outliers, such at Mount See also:Wellington near Hobart, and the See also:Eldon Range
.
This sheet of diabase has been regarded as Carboniferous; but, according to W
.
H
.
Twelvetrees, it is probably Cretaceous
.
The See also:Cainozoic system includes at Table Cape an outcrop of marine beds probably of Oligocene age
.
Lower Cainozoic lacustrine beds with fossil See also:plants. of the same age as those which underlie the older basalts of Victoria, occur in the valleys of northern Tasmania
.
The Cainozoic series includes many igneous rocks
.
The tinguaites and sfilvsbergites of Port Cygnet, south of Hobart, may be of this age; they are intrusive in Carboniferous rocks, and there is no See also:evidence of their precise date; but their resemblance to the rocks associated with the geburite-See also:dacite of Victoria suggests that they may belong to the beginning of the Cainozoic volcanic period of south-eastern Australia
.
North-western Tasmania in See also:Pleistocene times had an
of See also:Ross-See also:shire and See also:Inverness-shire in See also:Scotland, from the picturesque See also:character of the See also:blue, See also:
C.)
See also:Geology.—Tasmania is, geologically, an outlier of the Australian continent
.
It is most intimately connected with Victoria, from which it was only separated by the foundering of Bass's Strait in See also:late See also:Pliocene or See also:early Pleistocene times
.
The precise date of the separation is fixed as later than the See also:Miocene, since the fringe of the marine Miocene deposits along the southern coast of Victoria is broken, from Flinders to Alberton; and this See also:gap was no doubt due
Strait are the Tamar, See also:Inglis, See also:Cam, Emu, See also:Blyth, Forth, See also:Don, Mersey, See also:Piper and Ringarooma
.
The Macquarie, receiving the See also: At its greatest elevation it is comparatively level, and contains many extensive See also:freshwater basins, such as Lake See also:Augusta, Lake St Clair, Lake Sorell, Lake See also:Echo, Lake See also:Crescent, Arthur's Lake and the Great Lake . The marginal crests of this mountain tableland, together with its upper See also:surface, are known locally as " Tiers," and have a very commanding aspect in the neighbourhood of See also:Longford, See also:Westbury, Deloraine and Chudlcigh . The extent of the principal elevated plateau is best appreciated when we consider that it maintains its See also:general See also:altitude in a See also:westerly direction from Dry's Bluff (4257 feet) on the north to See also:Cradle Mountain (5069 feet) in the north-west, a distance of nearly 5o miles; from Dry's Bluff in a south-westerly direction to Denison Range, a distance of over 6o miles; and from Dry's Bluff to Table Mountain in a southerly direction, a distance of above 43 miles . This plateau itself again rests upon a more extended tableland, stretching westwards, and, with the See also:Middlesex Plains, the See also:Hampshire Hills and the Emu Plains, maintaining an altitude of 1200 to 2000 feet . Its limits follow the coast-line more or less closely, the space between it and the sea often broadening out into low-lying tracts not much raised above the sea-level . Here and there, rising abruptly from its surface, are to be seen isolated peaks, the most characteristic of which are See also:Valentine's See also:Peak (3637 feet) and Mount Pearse . Ridges and plateaus of a similar character, but more or less isolated, such as See also:Ben See also:Lomond (5010 feet) and Mount Wellington (4166 feet), are to be found in the north-east and south-west of the island . Towards the extreme west and south, anticlinal and synclinal ridges trend north and south, the most characteristic being the See also:Huxley, Owen, See also:Sedgwick, See also:Franklin and Arthur Ranges . See also:Settlement of See also:population has taken See also:place principally among the plains and lower levels of the north-western, midland and south-eastern parts of the island, following in the main the rocks of See also:Tertiary and Mesozoic age . In the See also:Recent Tertiary period the soils of these plains and valleys have been greatly enriched by extensive outbursts of See also:basalt with accompanying tuffs . These basalts produce a very rich See also:chocolate See also:soil, and were it not for their See also:influence, the greater part of what is now the most fertile part of the island would have been comparatively poor or altogether sterile . The See also:appearance of the island throughout is wonderfully beautiful, with its open plains, bordered by far-extending precipitous mountain tiers, its isolated shaggy peaks and wooded ranges, and its many See also:noble rivers and lakes . Its coasts for the most part, especially towards the south, See also:ate bold, and frequently indented with splendid bays and harbours, affording ample shelter and safe anchorage for See also:ships . On the western side onto is reminded of scenes in the See also:highlands extensive series of glaciers, of which the lower moraines were de-posited only about 400 feet above sea level . The See also:information as to the geology of Tasmania up to 1888 is collected in R . M . See also:Johnston's Systematic See also:Account of the Geology of Tasmania, which gives a bibliography up to that date . A later See also:sketch of the island is by W . H . Twelvetrees, " Outlines of the Geology of Tasmania," Proc . R . See also:Soc . Tasmania, 1900-1901, pp . 58-74 . The mining literature is given in the reports of the Mines See also:Department, and See also:special reports issued in the See also:Parliamentary Papers; and the economic and general geology are described in reports issued periodically by the Geological Survey, under W . H . Twelvetrees, and in papers published in the Proceedings of the Royal Society of Tasmania . The Mount Lyell mining field is described, with some account of the neighbouring districts of Western Tasmania, in J . W . See also:Gregory, The Mount Lyell Mining Field (See also:Melbourne, 1904) . The glacial geology, with a See also:summary of the literature thereon, is described by the same writer in the Quarterly See also:Journal of the Geological Society, 1904, vol . Ix., pp . 7-8, 37-53• (J . W . G.) See also:Climate.—Tasmania possesses a very temperate and healthy climate . The mean temperature of the See also:year, as estimated from observations extending back to 1841, is about 50.10° . The mean at Hobart was 54'4°, at Launceston 56.6° and at Oatlands, which is in the centre of the island and 1400 ft. above sea-level, 51.76° . See also:Snow is rarely seen except in the mountains . The See also:average temperature at Hobart of See also:January, the hottest See also:month, is 63°, and of See also:July, which is See also:mid-See also:winter, 45° . The western prevailing winds—particularly the north-western--carry the See also:rain-bearing clouds . The elevation-See also:divide between the western and eastern parts of the island rises generally to a height of between 3000 and 5000 ft., and consequently the parts to the east of such heights receive much less precipitation than those to the westward . The general average for the eastern See also:district over a period of years was 22.07 inches; for the western, 37.55 inches; and for Tasmania 26.69 inches . See also:Flora.—The vegetation which prevails among the older schistose rocks of the west and extreme south presents a totally different appearance to that which occurs in the more settled districts of the east . The western vegetation, as compared with that of the east, presents as marked a contrast as do the prevailing rocks upon which it flourishes . The characteristic trees and shrubs of the west include the following genera, viz.: Fagus, Cenarrhenes, Anodopetalum, Eucryphia, Bauera, Boronia, Agastachys, Richea, Telopea, Grevillea, Orites, Athrotaxis, Dacrydium, Phyllocladus . On the eastern side the plains and rocky ridges, where not artificially cleared, are occupied by shaggy and often sombre forests mainly composed of the following genera: See also:Eucalyptus (See also:gum See also:tree), See also:Casuarina, Bursaria, See also:Acacia, Leptospermum, Drimys, Melaleuca, Dodonaea, Notolea, Exocar pus, Hakea, Epacris, Xanthorrhoea, Frenela . The mountain slopes and ravines of the east have a well-marked vegetation . In character it is more akin to, and in many cases identical with, that of the west .
The tree See also:fern (Dicksonia antarctica) in the mountain ravines is especially remarkable
.
The following genera are also found in such positions in great luxuriance, viz.: Fagus, Anopterus, Phebalium, Eucalyptus, Richea, Cyathodes, Pomaderris, Prostanthere, Boronia, Gaultheria, See also:Correa, Bedfordia, See also:Aster, Archeria, Atherosperma, &c
.
In the extreme west the trees and larger shrubs do not appear to ascend the schistose rocky mountain slopes of the central and eastern parts
.
Fauna.—See also:Animal See also:life in Tasmania is similar to that in Australia
.
The dingo or See also:dog of the latter is wanting; and the Tasmanian See also:devil and See also:tiger, or See also:wolf, are See also:peculiar to the island
.
The Marsupials include the Macro pus or See also:kangaroo; the opossums, Phalangista vulpina and P
.
Cookii; the See also:opossum-See also:mouse, Dromicia nana; Perameles or See also:bandicoot; Hypsiprymnus or kangaroo See also:rat; Phascolomys or See also:wombat; while of See also:Monotremata there are the See also:Echidna or See also:porcupine See also:ant-eater and the See also:duck-billed See also:platypus
.
The marsupial tiger or Tasmanian wolf (Thylacinus cynocephalus), 5 ft. See also:long, is yellowish See also: The tail is thick, and the See also:bull-dog mouth is formidable . Among the birds of the island are the See also:eagle, See also:hawk, See also:petrel, See also:owl, See also:finch, peewit, See also:diamond bird, See also:fire-tail, See also:robin, emu-See also:wren, See also:crow, See also:swallow, See also:magpie, blackcap, See also:goatsucker, See also:quail, ground dove, See also:parrot, See also:lark, mountain See also:thrush, See also:cuckoo, wattlebird, whistling duck, See also:honey-bird, Cape Barren See also:goose, See also:penguin duck, waterhen, See also:snipe, See also:albatross and laughing jackass . See also:Snakes are See also:pretty plentiful in scrubs; the lizards are harmless . See also:Insects, though similar to Australian ones, are far less troublesome; many are to be admired for their great beauty . Population.—At the beginning of 1905, the state contained i8i,See also:ioo See also:people, giving a See also:density of 6.9 persons per square mile . The population in 187o was roo,765 . The See also:discovery of Mount Bischoff one year later, though it greatly stimulated See also:speculation and induced a large influx of immigrants, did not put a stop tothe outflow, for in 188o the population was still below 115,000 . During the next two decades there was a substantial advance; in 1890 it had reached 145,200, and in 1900, 172,980 . Like all the Australian states, Tasmania shows a decline in the See also:birth-See also:rate; in 1905 the births were 5256—36 less than in 1904—which gives a rate of 29.32 per See also: |