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beyond its proper dimensions by mountainous floods, nor contracted by summer droughts. From its being at least four times larger than it is at Bathurst, even in a favourable season, it must have received great accessions of water from the mountains north-easterly. '— pp. 184-6.

For five days they proceeded down the banks of this enchanting river; sometimes contracted between rocky cliffs; sometimes expanded between forests, or hills clothed with the most luxuriant grass to the very summits. The timber was various and excellent. Limestone, slate, and granite overhung the river, everywhere navigable for boats; and confined, in its highest inundations, by secondary banks, which operated as a complete security to the contiguous land. A great number of streams from either bank empty themselves into the Macquarie. Fish and game were found in great abundance. On the 24th, they quitted the banks of the river, and, on the 29th, arrived at Bathurst, after an absence of nineteen weeks.

Such a description as Mr Oxley brought back of the parts of the Macquarie he had seen, it was impossible to put up with. An universal joy was diffused over the whole colony. Larceny reared her drooping head; the Children of the Antient Bailey magnified themselves into importers and exporters; and thought they were at last within the reach of wealth, which no jury could find guilty, and no judge punish with the rope of the law. Forth went the indefatigable Oxley, and, with him, the usual apparatus of dogs, bat-horses, boats, and instructions signed (perhaps read) by Lord Bathurst. Their journey was begun on the 5th of June, from nearly the same spot where they had at first touched upon the Macquarie in their former expedition. From this period till the 25th of June, the river Macquarie appeared to be much the same as they had found it at first: the country not perhaps quite so good; but fully entitled to be considered a land of great promise and fertility. The only new useful substances they found upon the banks, were fullers' earth and freestone. On the 23d, the expedition began to quake, and the Macquarie to lose the character it had hitherto maintained. The gravelly beaches and rocky points disappeared; the banks became lower; and in many parts, the floods swept over them. A second Lachlan began to be suspected.

They had scarcely gone six miles, on the 26th, before they perceived the waters spreading over the plain on which they were travelling, and that with a rapidity which reduced their safety to a fair trial of speed between them and the river. They gained a secure place; and from thence Mr Oxley, with two or three men, proceeded down the river in a small boat.

"After going about twenty miles, we lost the land and trees. The channel of the river, which lay through reeds, and was from one to three feet deep, ran northerly. This continued for three or four miles farther; when, although there had been no previous change in the breadth, depth, and rapidity of the stream for several miles, and I was sanguine in my expectations of soon entering the long sought for Australian sea, it all at once eluded our farther pursuit by spreading on every point from north-west to north-east, among the ocean of reeds which surrounded us, still running with the same rapidity as before. There was no channel whatever among those reeds, and the depth varied from three to five feet. This astonishing change (for I cannot call it a termination of the river), of course left me no alternative but to endeavour to return to some spot, on which we could effect a landing before dark. I estimated that during this day we had gone about twenty-four miles, on nearly the same point of bearing as yesterday. To assert positively that we were on the margin of the lake or sea into which this great body of water is discharged, might reasonably be deemed a conclusion which has nothing but conjecture for its basis; but if an opinion may be permitted to be hazarded from actual appearances, mine is decidedly in favour of our being in the immediate vicinity of an inland sea, or lake, most probably a shoal one, and gradually filling up by immense depositions from the higher lands left by the waters which flow into it. It is most singular, that the high lands on this continent seem to be confined to the sea-coast, or not to extend to any great distance from it. pp. 243-4.

It does not exactly appear from this narrative, why Mr Oxley stopped and turned back. He was victualled for a month, and had only been out three days; he had from three to five feet water; and his boat did not, as he says, draw more than one foot. The waters set strongly to the north. He thought himself upon the eve of entering a great inland sea. Twenty or thirty miles further would in all probability have determined the point. Possibly the reeds may have been so thick, that it was impossible either to pull or push the boat any further. If this were the case, he should in justice to himself have said so. At present, we know that he had arrived at the point where geographical curiosity was on the very point of receiving its gratification; yet we remain as ignorant as we were before, and unable to divine why our darkness has not been illumined. We dare to say Mr Oxley can give very good reasons—but he does not give them in his book.

From this point the expedition returns, in a direction nearly east, to the coast, and in the parallel of 31-20 south latitude. By the 26th of August, they had reached a good fertile_country, where water ran, and kangaroos hopped-where the eye.

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 34° 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

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 gas 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 prepared some at the laboratory of the Royal Institution,—and the heaviest 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 therefore 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 olefiant, 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 has 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 foreign 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. Hence, if this increase is caused by the olefiant gas being changed by decomposition into double its bulk of hydrogen, it plainly fol

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