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quartz are large, these are sometimes entirely filled up with gold; and not unfrequently irregular holes and crevices seem to have been formed in the quartz by decomposition or rottenness, which have sometimes been subsequently filled with gold. In such cases, the gold often assumes irregular forms, such as melted lead will when poured into water-forms which have given people the idea of the gold having been deposited in a state of fusion, a notion in all probability utterly unfounded. How the gold got into the quartz, is a point at present so uncertain, that no man of science would take upon himself the responsibility of answering the question. The size of the irregular lumps thus entangled in the quartz varies greatly, the largest hitherto known single lump in the world being a Russian one, weighing 78 pounds avoirdupois, equal to 1137-5 Troy ounces. It is, however, usually found in small flakes, grains, and dendritic strings, weighing only a few grains.

Now, geologists tell us, that not only have large portions of the solid rocks forming the crust of the globe been formed beneath the sea, and lifted up subsequently into the air, during which process many of them were penetrated by great masses of molten rock, and baked, hardened, fractured, contorted, dislocated, and altered, but that, since all that took place, and since the veins, metalliferous and otherwise, were formed in the rocks, that which was once land has been again depressed beneath the sea, and subject to the wearing action of its waves, and again lifted up to form dry land. This may have occurred not once only, but many times, during that immense series of ages which have elapsed since the early rocks were formed-a series too vast, probably, for the human mind to form even a rough notion of.

Now, the last time the land of every country on the earth slowly rose from beneath the sea, it must of course have been subject to the degrading and destructive power of the breakers, and of the waves and tides and currents, and all that wearing action we now see going on on our own shores daily and hourly before our eyes. The consequence is, that portions of every rock, large or small, have been broken off, washed and dashed about upon beaches, or under shallow water, rolled into pebbles, pounded into sand, or ground down into mud and clay. These pebbles, sand, mud, and clay, have been transported by these moving waters often to great distances from their parent site, the largest and heaviest being generally removed the least distance, but the finer and lighter particles swept sometimes tens, sometimes hundreds of miles away from the rock they were first broken off. Such is the origin of all the mud, clay, sand, gravel, and other loose and incoherent materials we so commonly find beneath the surface in all countries when we dig below the soil, interposed between it and the main body of the solid rock* below. Some

*By rock here, we mean any large regularly formed mass of earthy matter, whether it be hard or soft.

times these accumulations are entirely wanting, even over large spaces; sometimes they are but a few inches thick, often but a few feet; but occasionally they occur in masses 100 or 150 feet in thickness. They are disseminated with great irregularity, sometimes lying on the tops, or resting on the sides of hills of considerable elevation; but most frequently we find them in the valleys, and in the lowest levels of a country, whither moving` water would have, of course, the greatest tendency to sweep them. We need hardly stop to remark, that all the present rivers of any country, from the tiniest rill upwards, naturally seek these same valleys and low levels, and are continually helping, therefore, to carry down 'drift,' sand, gravel, or clay. Not a shower that falls and 'muddies' our brooks and rivers, but is a helper in this process.

Now, whenever the moving waters of the sea, by which these drift-materials were thus formed and deposited, attacked rock containing gold, it would of course break off lumps of it, just the same as any other rock, and equally wash, roll, and knock it about, and thus break it up into smaller fragments, round it into pebbles, and grind it into sand. In this way, much of the gold would be knocked out of the rock, and much water-worn gold accumulated, or water-worn fragments of gold and quartz together.

From this point of time, however, there is a remarkable difference observable in the action of the water on the gold, and on rock which contains no gold. All kinds of rock, or earth, or stone, at all events all the common kinds, are pretty nearly of the same specific gravity—that is to say, of the same weight, bulk for bulk. Chalk, clay, limestone, compact sandstone, granite, marble, basalt, have all specific gravities varying from 2 to 3 -that is to say, they are twice or thrice the weight of their bulk of water. Pure gold, however, has a specific gravity of 19, or is nineteen times as heavy as its bulk of water; and the most impure ore of gold that occurs in nature, has at least a specific gravity of 12 or 15. Gold, then, is about six or seven times as heavy as quartz, or any other stone it is likely to be associated with. The consequence of this is, that moving water has at least seven times less power over it, less power to move it along, either suspended in the water or rolling along its bed.* When the drift, therefore, was formed, vast quantities of stone might be removed to great distances, while the gold was left behind, not far from its native site. All the large lumps of gold will certainly be but little removed, as also all the large lumps of quartz heavily freighted with gold. Grains of gold and small fumps may be carried further, while scale-gold and fine dust, especially if flat and thin, may be carried to very considerable distances, and

*We shall see this more clearly, perhaps, when we reflect, that stone suspended in water loses one-third of its weight; but that gold suspended in water loses only one-nineteenth of its weight.

spread far and wide over a large surface of ground. If there was any place near an auriferous vein where the currents of water were checked from any cause-such as a deep hole, or a meeting of two streams, or any eddy caused-such a place would be likely to have a very rich mass of drift deposited there, as the gold would be the first substance to fall down under such circumstances. It follows from these considerations, that in any country the rocks of which contain gold, the drift will likewise contain gold; and that the whole mass of the drift in the neighbourhood of the auriferous rocks will be richer in gold than the whole mass of the rocks from which it was derived, much of the broken rock having been removed to a vast distance, while the gold was left behind.

It follows, moreover, that of all the drift-sand, gravel, and mud of any country, that found in the bed of a river is likely to be the richest, because the river has been constantly engaged in resifting, washing, and sorting the materials formerly sifted by the sea that formed the drift, carrying forward all the lighter portions still further away, but leaving the gold in all the deep pools, or holes, or eddies, on all the sand-spits, or against all the rocky bars, or wherever the swiftness and strength of its stream is most likely to be checked.

Now, gold appears to be about the most widely diffused of all metals, with the exception of iron, on the face of the globe. Hardly a granitic and metamorphic district is known on the earth, that has not at one period or other yielded gold. It is, therefore, a pretty safe prophecy, when a new and unexamined district of granitic and metamorphic rocks is discovered, to foretell its probable auriferous character. It has been remarked by Humboldt and others, that most of the auriferous mountain-chains run in a north and south direction. This is very likely, because most of all the great mountain-chains of the globe have that direction. That the meridional direction, however, has anything to do with the production of gold, is not only à priori unlikely, but is disproved by the fact of gold not being confined to such meridional mountain-ranges.

It has even been publicly suggested by an Australian writer on the gold-districts of that country, that some particular meridians were more likely to be productive of gold than others—one of those meridians being that of 148 degrees east longitude, if we recollect rightly. Such vague, dreamy speculations, resting on no other foundation than one or two half-perceived, half-fancied analogies, are the bane of true science. We will therefore dismiss, with no further notice, all the prophecies, whether scientific or otherwise, as to the probable auriferous character of the Australian rocks.

The discovery of gold in Australia, like that of California, was reserved for an individual who proceeded upon no scientific view of the subject. Mr Edward Hargreaves, having had a farm on the flanks of the Conobolas, some thirty miles west of Bathurst, went to

California in search of gold. While there, he was struck with the similarity between the rocks and earthy matters of California and those of his own district. He returned, accordingly, to Australia, ' prospected' in his own neighbourhood, and after one or two month's search (April 1851), found some gold. Unless we imagine the whole metamorphic and granitic rocks of the great eastern chain of Australia, from the south-west cape of Van Diemen's Land to Torres Strait, to be equally rich in gold, it is evident that his finding an auriferous district, even in two months' time, was a lucky accident. Moreover, unless it turn out that the high lands of Western Australia, or Swan River District, are likewise auriferous, we must still look upon it as a chance that gold was found at all in the eastern chain, because the rocks and all the apparent geological conditions of those two districts are precisely

the same.

Being assured of the valuable nature of his discovery, Mr Hargreaves applied to the colonial government for reward; and on his report being verified by Mr Stutchbury,* the_colonial geologist, Mr Hargreaves was rewarded by a bonus of L.500, and an appointment as 'Commissioner of Crown Lands for the Exploration of Gold Districts'-his salary and allowances being L.920 per annum.

The excitement of course became intense throughout the colony of New South Wales, and spread rapidly into that of Victoria. People, many of them ill provided and ill suited for the work, rushed to the gold-diggings; wages rose to great rates; and the prices of provisions to extravagant heights. It was soon found, however, that gold-digging was hard and weary work, and that, carried on without proper preparation of tools and division of labour, without shelter and with scanty food, it was too much either for the health, the strength, or the resolution of most people to endure. A considerable reaction took place accordingly, and wages and food sank again nearly to their original prices in New South Wales. A slight accession of the gold-fever occurred, in consequence of the discovery of a hundredweight of gold, or L.4000 worth in one block, on the Murroo Creek, fifty miles north of Bathurst; but since then, gold-digging seems to have assumed in New South Wales the character of a regular steady occupation, taken up by those best adapted to it, and by them pursued as almost a permanent employment.

The finding of a hundredweight of gold is so singular a

*We observe that Mr Stutchbury was subject to an official reprimand from the governor, as to his not reporting on the gold, and ordered to go in search of it. Now, we must distinctly protest against its being supposed that it is any but a very small part of the duties of a geological surveyor of any country to hunt for mineral veins or for drift-metal. His business is to map the surface boundaries of all the different formations, and to note their appearances, so as to give an account of the solid structure of the whole country. As a result of this survey, will come out the knowledge of the districts in which it is possible for mineral veins to occur, and many other useful pieces of information, that would never be discovered by the mere metal or mineral hunter.

circumstance in the world's history, that a particular account of it may be acceptable. In the first week of July [1851], an educated aboriginal, formerly attached to the Wellington Mission, and who has been in the service of W. J. Kerr, Esq., of Wallawa, about seven years, returned home to his employer with the intelligence, that he had discovered a large mass of gold amongst a heap of quartz upon the run whilst tending his sheep. He had amused himself by exploring the country adjacent to his employer's land, and his attention was first called to the lucky spot by observing a speck of some glittering yellow substance upon the surface of a block of the quartz, upon which he applied his tomahawk, and broke off a portion. At that moment, the splendid prize stood revealed to his sight. His first care was to start off home and disclose his discovery to his master, to whom he presented whatever gold might be procured from it. As may be supposed, little time was lost by the worthy doctor. Quick as horseflesh would carry him, he was on the ground; and in a very short period the three blocks of quartz, containing the hundredweight of gold, were released from the bed where, charged with unknown wealth, they had rested perhaps for thousands of years, awaiting the hand of civilised man to disturb them.

"The largest of the blocks was about a foot in diameter, and weighed 75 pounds_gross. Out of this piece, 60 pounds of pure gold were taken. Before separation, it was beautifully incased in quartz. The other two were something smaller. The auriferous mass weighed, as nearly as could be guessed, from two to three hundredweight. Not being able to move it conveniently, Dr Kerr broke the pieces into small fragments, and herein committed a very grand error. As specimens, the glittering blocks would have been invaluable. Nothing yet known of would have borne comparison, or, if any, the comparison would have been in our favour. From the description given by him, as seen in their original state, the world has seen nothing like them yet.

The heaviest of the two large pieces presented an appearance not unlike a honeycomb or sponge, and consisted of particles of a crystalline form, as did nearly the whole of the gold. The second larger piece was smoother, and the particles more condensed, and seemed as if it had been acted upon by water. The remainder was broken into lumps of from two to three pounds and downwards, and were remarkably free from quartz or earthy matter.

"In the place where this mass of treasure was found, quartzblocks formed an isolated heap, and were distant about one hundred yards from a quartz-vein which stretches up the ridge from the Murroo Creek. The neighbouring country has been pretty well explored since the discovery, but, with the exception of dust, no further indication has been found.

'In return for his very valuable services, Dr Kerr has presented the black fellow and his brother with two flocks of sheep, two saddle-horses, and a quantity of rations, and supplied them with a

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