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pursuit of the same liberal system, which has already organised the Geological Ordnance Survey in the United Kingdom.
The " Economic Geology" might thus become the centre of a geological survey, not only of the British islands, but of the British empire; and might include, within its already valuable museum, all the specimens relative to the colonies; thus concentrating within its walls the information which now must be sought for in remote and widely distant regions.
To achieve any complete geological survey of such countries—as, e. g., New South Wales and Van Diemen's Land—by private enterprise, is out of the question. Besides the expense, time, and labour, which such a task requires, and the necessary means of publishing the results which it needs, there is one insuperable difficulty in the way of a private individual, from the simple fact of his entering on the field of his researches in a private capacity. His functions ought to be official; not because an official character would carry, in matter of science, greater weight and authority than private and well-known skill, but because the official geologist would find unrestrained access to every nook of the country to which his inquiry would lead him, and would be placed at once above that suspicion, by which the inhabitants of every new country are inclined to question the purity of the intentions that actuate the naturalist, often rendering his progress unpleasant, and sometimes dangerous.
The present geological outline, thus constructed, as it has been, from materials comparatively scanty, and gathered under many disadvantages, cannot be better concluded than by borrowing a passage from an admirable essay, on a subject of the highest importance. *
* Essay towards a First Approximation to a Map of Cotidal Lines, by Professor Whewell.
"I should regret its publication, if I supposed it likely that any intelligent person would consider it otherwise than an attempt to combine such information as we have, and to point out the want, and the use of more; I shall neither be surprised, then, nor mortified, if the outline which I have drawn turns out to be in many instances widely erroneous."
CLIMATOLOGY OF NEW SOUTH WALES AND VAN DIEMEN'S LAND.
Next to the science of geology, there is no part of physical geography which ranks higher, or claims greater attention than meteorology; though as yet, notwithstanding its connection with the most essential studies of natural philosophy, and with the most vital concerns of mankind, the state of this science is such, that, beyond a mere collection of simple facts, and of registers recorded patiently, yet without the guidance of any satisfactory theory, no contribution of superior character, tending to any deductive reasoning, can legitimately be made to it. The mode even of exhibiting such facts, so that they may be placed in harmony with the general laws of physics, and in the pre-eminence corresponding to their climatic agencies and influences, is still attended with considerable difficulty.
In the following disquisition on the climate of New South Wales, and Van Diemen's Land, the plan adopted has been, to trace that climate to its proper attendant causes; to analyse separately, so far as is possible, these causes and their effects, together with their mutual dependence on each other, and the share each of them bears in the economy of nature. Thus, atmospheric currents, winds, atmospheric pressure, calorific effect of solar rays, terrestrial absorption, and radiation of heat, diaphaneity of the atmosphere, evaporation, rain, and temperature, have all been alternately reviewed, and their respective and collective agencies investigated.
An attempt has next been made to link the isolated effects into one expressive or connected group, and to give, if possible, an approximate general idea or picture of that bountiful climate with which the two colonies have been gifted.
The numerical elements which have guided the writer in this investigation were obtained during five years, ending with 1842 inclusive. They were derived, —
1st From the meteorological register of the barometer, thermometer, rain and wind, kept by the assistant commissary, Mr. Lempriere, in Port Arthur, Van Diemen's Land; the number of observations being - - 21-600
2dly. From two separate registers, one kept at Circular Head and the other at Woolnorth, the estate of the Van Diemen's Land Company, and embracing observations similar to those of Port Arthur, to the number of - 43*200
3dly. From three separate registers kept at Port Macquarie, Port Jackson, and Port Philip (New South Wales), by order of the Colonial Government, and including observations of the barometer, thermometer, hygrometer, wind and rain, to the number of - - - 25-gOO
4thly. From my own register of the barometer, hygrometer, thermometer, solar and terrestrial radiation, evaporation, diaphaneity, rain, winds and currents, of which the observations amounted to .... 17"280
Total - - - 107-980
To the above 107*980 numerical elements must be added those which resulted from simultaneous observations of phenomena made in different localities of the two colonies, and in which I was aided and assisted by some friends, and by none more than my enlightened and valued friend, Capt. P. P. King, R. N., who not only took his share in these labours, but gave me free access to his own meteorological register, kept for years in New South Wales; and, which was not less important, kindly condescended to give his opinion on the section when it was completed. I may add, that the approval of it by that able judge and keen observer, in April, 1843, has operated as one of the leading motives for its present publication.
ATMOSPHERIC WTNDS AND CURRENTS.
To the facts connected with winds and currents, so admirably collected and reasoned upon by Dove, in his Meteorologishe Untersuchungen; by Schouw, Beitrdge zur Vergleichenden Klimatologie; by Redfield, in his valuable observations On Hurricanes; and by Colonel Reid, in his not less valuable work On Storms,—'a few additional data, derived from personal observations, in different parts of the world, are here added; some, as corroborating what the above-named eminent meteorologists have already noted; some, as new phenomena, tending to extend our still limited knowledge of the subject.
Considered merely in relation to New South Wales and Van Diemen's Land, and to the influence they exercise upon the climate, the atmospheric winds and currents present themselves to the observer as foremost in rank amongst climatic agencies.
Their respective actions, manifestly of various character and various intensity, appear in some instances to be mere expressions of an accidental perturbation in the atmospheric circulation; in some others, their periodical return, and uniform course, direction, force, and succession, show that they are governed by a law as immutable as that which regulates the course of seasons; while in other instances, again, their movements is of a subordinate character, like that of an eddy, depending upon the direction and intensity of a stronger current.
In all cases, however, their action on the climatic changes is so ramified and complicated in its agency