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was gratified, and the belly filled. In their way thither, they passed a large and impetuous river, to which they gave the name of Castlereagh. Why grandeur and impetuosity should have brought to their recollection this polished Member of the Cabinet, we do not exactly perceive; but we cannot help admiring the officiality of the nomenclature. There is hardly now a clerk in the pay of Government, who has not some portion of land named after him in Botany Bay.

In their way to the sea, they pass over hills 3000 feet high, with good pasture up to the very summit; and look into glens 3000 feet deep, three miles broad at the top, and sloping to 100 feet at the bottom. On the 23d of September they saw the sea from the top of the mountains; and upon the coast discovered a good harbour for coasting vessels. Their journey was finished at Sydney on the 5th of November. It is very remarkable, in so mild a climate, in such a latitude, and with such plenty of fish and game, that they should have found the countries through which they passed so badly peopled. Mr Oxley attributes this circumstance in some measure to the great want of ingenuity in the natives. They cannot kill kangaroos, except by some lucky accident ;-they cannot catch fish ;-they live by necessity upon rats and squirrels. Whatever the fertility of New Holland may be, it contributes little more than this reptile fecundity to their support. Why the New Hollanders are so inferior to other savage nations in the arts of life -why they cannot fish like the New Zealanders-why they do not catch large animals in traps, or shoot them with arrowswhy they are only elevated a few degrees in capacity above these animals which they cannot kill, --we do not presume to conjecture. There is no other instance of such an intellectual state in the midst of such physical advantages. It must be considered as a prodigious advantage to this country, that rabid tygers, and the cruel seeds of lions, are absent. This makes the thinness of population more surprising. The most noxious animals appear to be native dogs: they are very mischievous to sheep.

The result of these two journies is certainly very singular. All the water falling on the west side of the Blue Mountains, between 30° and 34o S. latitude, and all the streams on that side of this great dividing range, seem to be employed for the formation, as far as we know at present, of one immense marsh, receiving the alluvial matter poured into it from the higher grounds. The Lachlan river, one of the main carriers, receives no tributary streams for a course of 1200 miles, but pours into

A land expe

the marsh the original water which it received at the commencement of its course almost neat as imported. The other main channel, the Macquarie, passes through a well watered country; collects all the tributary rivers; and pours them, in the same way, into the great muddy magazine. "The curious points now are, to discover whether ihese immense supplies of water do not end in an inland sea; and whether this inland sca, if it exists, has any communication with the ocean. The nearest part of the coast about Cape Bernouilli, is distant 180 miles from the farthest part of the Lachlan reached by Mr Oxley in his first expedition ; by which expedition it is clearly demonstrated, that no great river flows from the eastward into the sea between Cape Otway and Spencer's Gulf. dition from the eastern part of Spencer's Gulf, would soon determine the fate of the western side of the Lachlan Marshes. The waters of the Macquarie point to the north-west; and the promised sea of Mr Oxley may there perhaps penetrate deeply into this fifth quarter of the globe. The solid gain to the Colony is the disclosure of a beautiful tract of land, for 200 or 300 miles on the Macquarie, and the discovery of a good port to the north of Port Jackson.

This publication is not well drawn up; and the maps are indifferent. At the end are some Statistical Tables, by which it appears that the population of New South Wales has increased from 13,000 in the year 1815, to 17,000 in the year 1817, and to 22,000 in the year 1818; and that, with the population of Van Diemen's Land, the total amount is 25,000. In spite of this increase of population, the cleared land has diminished from 93,000 acres in 1817, to 44,000 acres in 1818; while the total of land held has increased, in the same period, above 60,000 acres. We are totally unable to account for this diminution of the cultivated lands. The Colony possessed in the year 1813, 12,000 horned cattle; in 1817, 33,000 ditto; in 1818, 40,000 ditto. In the same periods, the horses were 1800, 2800, 3300. The sheep were 45,000, 66,000, 73,000. The pumber of sheep returned from Van Diemen's Land is 128,000; this is quite astonishing. The hogs are, in the same periods, 14,000, 15,000, 22,000.-So that every thing which cultivated land supports has increased : Cultivated land, however, is said to have diminished more than one half. We suspect some false print-but we give the Tables as we find them; and there is no correction in the errata.

ART. IX. The Bakerian Lecture. On the Composition and

Analysis of the Inflammable Gaseous Compounds resulting from the Destructive Distillation of Coal and Oil ; with some Remarks on their relative Heating and Illuminating Powers. By W.T. BRANDE, Esq., Sec. R. S. Prof. Chem. R.I. From the Philosophical Transactions for 1820.

IT
T can hardly be laid to our charge, that a considerable period

has elapsed since any thing relating to Chemical inquiry has appeared in this Journal: For in fact, the labours of persons learned in that department of science, have lately furnished but little matter for speculation. The discoveries of Sir Humphry Davy-splendid in every sense of the word, and not less reniarkable for the brilliancy than for the rapidity with which they were produced-have made us perhaps too unreasonable; and caused us to form an estimate of the labours of those who have succeeded him, less favourable than they really deserve. We have been spoilt by plenty ;-and because every year does not give birth to some great discovery, we exclaim that there is a famine in the land. Although Mr Brande, who succeeded Sir H. Davy in the Royal Institution, has been less successful than his great predecessor in the path of discovery, his researches, and, above all, his skill in analytical operations, have done much for Chemistry in general; and we willingly take this opportunity of bearing witness to the utility of labours which—however great their excellence and intrinsic value

may be—are too apt to be passed over without due estimation, because they happen to be wanting in originality and invention.

The paper before us contains some observations and experiments made on the inflammable gases used for the purposes of illumination. The inquiry was undertaken, in the first instance, with a view of ascertaining the mixture and quality of the gases best suited for such purposes; and as some novelties relative to the constitution of the gaseous compounds presented themselves in the course of the investigation, Mr Brande conceived the matter to be of sufficient importance to form the subject of the Bakerian Lecture.

When pit-coal is distilled, and the products collected in proper vessels, they are found to contain, besides other substances, a highly elastic fluid, which was long supposed to consist of two gases, compounds of carbon and hydrogen ;-the one called the heavy hydrocarburet, or olefiant gus, the other,' light hydrocarburet. The first of these is composed of equal portions of carbon and hydrogen; the second, of one portion of VOL. XXXIV, NO. 68.

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carbon and two of hydrogen. Now, if we take hydrogen to be as 1, the specific gravity of the heavy, or olefiant gas, is 13.4, and that of light hydrocarburet is 7.7, or as .57363, assuming atmospheric air for unity. Upon examining the mixed coal gas, Mr Brande found its specific gravity as low as .4430. This he had obtained from the Gas-light Company's works at Westminster; but being aware that the density of this gas is various, according to the coal from which it is made, he pared some at the laboratory of the Royal Institution,--and the beaviest he met with was only.4940. He concluded then, that if coal gas were wholly composed of the two varieties of carburetted hydrogen, the specific gravity of the light hydrocarburet must have been estimated too high. To ascertain this, he procured some from acetate of potash, separated its carbonic acid by lime water, and found its specific gravity to be .687. It was thierefore evident that the whole constituents of coal

gas could not be the two hydrocarburets. Neither could a part of the mixture be the gaseous oxide of carbon, (which, according to Sir H. Davy is given out by coals in burning, and therefore might be introduced in the gas evolved during the distillation), because its specific gravity is .9834. Hence Mr Brande conjectured that coal gas must be a mixture of olefiant and hydrogen gases; and the experiments detailed in this paper are intended to confirm this opinion.

After detonating 100 measures of coal gas with 200 of oxygen by means of the electric spark over mercury, and absorbing the carbonic acid by liquid potassa, 36 measures of pure oxygen were found to remain in the tube. Hence 164 parts of

oxygen were required for the complete combustion of 100 parts of coal gas. Now, 100 parts of olefiant gas require 300 of oxygen, and 100 of hydrogen 50, for their respective combustions ; * so that, if we suppose 100 parts of coal gas to be composed of 45 of olofiant, and 55 of hydrogen, the quantity of oxygen required for its perfect combustion will be very nearly 164 parts, and the mixture thus formed will have nearly the same specific gravity as the coal

gas.

* See Henry's Elements of Chemistry, Vol. I. p. 355.Where he also states that it requires 190 volumes of oxygen for the perfect combustion of 100 of coal gas. The difference between this result and that stated by Mr Brande, must be owing to the different qualities of the coal gases under examination. Yet the proportions of oxygen necessary for the saturation of 100 measures of olefiant and hydrogen gases, mentioned in Mr Brande's paper, are precisely the same as those given by Henry. We presume Mr Brande bas offered them as the results of his own experiments.

Before noticing the next step in Mr Brande's inquiry, we must advert to an experiment of Berthollet, by which the de composition of olefiant gas is effected in a very simple and beautiful manner. This is performed by passing the gas repeatedly through a tube heated to a very high temperature. In repeating the experiment, Mr Brande introduced 100 measures of olefiant gas--obtained by distilling alcohol and concentrated sulphuric acid-into a mercurial gasometer, connected with a second gasometer by means of a platinum tube, in which were placed some small crystals of quartz, previously heated to redness, for the purpose of increasing the heated surface over which the gas was to be passed. The tube was then heated to a very high degree of temperature, and the gas passed froin one gasometer to the other, until it ceased to dilate. The apparatus was then allowed to cool, and the volume of gas was found to be exactly doubled. This was detonated with an equal volume of oxygen, and the remainder proved to be half the volume of pure oxygen; showing that the olefiant gas had been reduced by this simple process of decomposition, into double its bulk of hydrogen. It also appeared that it had almost entirely parted with its carbon; for the oxygen which remained, scarcely rendered lime water turbid, and was not apparently diminished by exposure to liquid potassa. In the heated part of the tube there was a considerable deposition of charcoal. The apparatus remaining the same, 100 measures of coal

gas were introduced into the gasometer, and underwent the same precess. When cool, the gas was examined, and found to have increased 40 parts. It burned with a lambent flame, like hydrogen; and, when detonated over mercury, required very little more than half its volume of oxygen to render the combustion complete. Very little carbonic acid could be detected; and, as in the former experiment, the inside of the platinum tube was lined with charcoal. It appears, from this, very evident that, as the quantity of olefiant gas contained in the coal gas is measured by the increase in bulk, after the gas has undergone decomposition by heat; therefore, the 100 measures of coal gas contained 40 of olefiant gas; and if no foreigri gases were present, the remaining 60 measures were hydrogen.

Upon the same principle, similar conclusions are drawn from another experiment, in which a glass tube containing a little sulphur and 100 measures of coal gas, is subjected to a red heat until the gas suffers no further dilatation. The volume, when cold, is found to have increased to 140 measures. if this increase is caused by the olefiant gas being changed by decomposition into double its bulk of hydrogen, it plainly fol

Hence,

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