A System of Mineralogy, Volumen3

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A. Constable & Company, 1816
 

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Página 14 - And all King Solomon's drinking vessels were of gold, and all the vessels of the house of the forest of Lebanon were of pure gold; none were of silver, it was nothing accounted of in the days of Solomon.
Página 12 - The third principal tract where gold is abundant, lies on the south-east coast, between 15° and 22° of south latitude, and nearly opposite Madagascar. The gold of that country, it is said, is found not only in the state of dust, but also in veins ; and it is supposed, that Ophir, from which Solomon obtained gold, was a country on the same coast. Nearer to the equator, the Gold Coast supplied the Portuguese, and afterwards the Dutch, with great quantities of gold dust.
Página 101 - H5 and converting it into steel. There is no doubt that the axes and other Mexican tools were almost as sharp as steel instruments; but it was by a mixture with tin, and not by any tempering that they acquired their extreme hardness. What the first historians of the conquest call hard or sharp copper, resembled the xa*vit of the Greeks, and the Aes of the Romans.
Página 216 - I much suspect, that a predisposition to vitriolization, in these pyrites, is produced by a small portion of oxygen being previously combined with a part, or with the general mass, of the sulphur, at the time of the original formation of these substances, so that the state of the sulphur is tending to that of oxide, and thus the accession of a farther addition of oxygen becomes facilitated.
Página 12 - Desert, there are tracts remarkable for the quantity of gold they contain. Thus the flat country, which extends from the foot of the mountains in which are situated the sources of the Gambia, Senegal, and Niger, has from an early period afforded gold. Bambouk, which is situated to the north-west of these mountains, furnishes the greatest part of the gold which is sold on the western coast of Africa, as well as that which is brought to Morocco, Fez, Algiers, Cairo, and Alexandria. The gold, as is...
Página 51 - ... surface both in the mountain of Gualgayoc, which rises like a fortified castle in the midst of the plain, and at Fuentestiana, at Cormolache, and at la Pampa de Navar. In this last, plain for an extent of more than half a square league wherever the turf has been removed, sulphuretted silver has been extracted and filaments of native silver adhere to the roots of the gramina. Frequently the silver is found in masses (clavosy remolinos) as if smelted portions of this metal had been poured upon...
Página 101 - ... Werner conjectured that copper was the first metal worked by man, and Jamieson observes that " this opinion may be considered as very probable, especially when supported by the account which is given o*f some of the native tribes of the north-western parts of America, who, though little civilized, have applied to domestic purposes the native copper with which their country abounds. It is also known that at a very early period, domestic utensils and instruments of war were made of a compound of...
Página 101 - Macrobius, who wrote in the fourth century, informs us that when the Etruscans intended building a new city, they marked out its limits with a coulter of brass, and that priests of the Sabines were in the habit of cutting their hair with a knife of the same metal.* The Greek and Roman sculptors executed fine works of art in porphyry, granite, and other hard minerals by means of their copper instruments.
Página 13 - Gold veins have been found in the mountains of Guamoco and Antioquia ; but their working is almost entirely neglected. The greatest riches in gold obtained by washing are deposited to the west of...
Página 91 - Why is silver alloyed with copper for plate and coin ? Because, the former metal is thus rendered harder and more sonorous, while its colour is scarcely impaired. The silver mines of Mexico and Peru far exceed in value the whole of the European and Asiatic mines : for we are told by Humboldt, that three mines, in the space of three centuries, afforded 316,023,883 pounds troy of pure silver ; and he remarks that this quantity would form a solid globe of silver, 91,206 English feet in diameter.

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