Manual of Mineralogy and Lithology: Containing the Elements of the Science of Minerals and Rocks : for the Use of the Practical Mineralogist and Geologist and for Instruction in Schools and Colleges

Cover
Trubner & Company, 1879 - 474 Seiten
 

Andere Ausgaben - Alle anzeigen

Häufige Begriffe und Wortgruppen

Beliebte Passagen

Seite 109 - The pyrites when pounded are reduced to powder ; iron pyrites is too hard to yield at all to a knife, and copper pyrites affords a dull greenish powder. Moreover, the pyrites give off sulphur when strongly heated...
Seite 64 - ... the mineral in the ordinary way, with a delicate pair of scales : next sus- 98 pend the mineral by a hair or fiber of , silk to one of the scales, immerse it thus suspended in a tumbler of water, (keeping the scales clear of the water,) and weigh it again : subtract the second weight...
Seite 227 - Hungary, and other countries, there are artificial arrangements called 'nitriaries,' or nitrebeds, from which nitre is obtained by the decomposition mostly of the nitrates of lime and magnesia which form in these beds. Refuse animal and vegetable matter putrified in contact with calcareous soils produces nitrate of lime, which affords the nitre by re-action with carbonate of potash. Old plaster lixiviated affords about 5 per cent This...
Seite 223 - Cracow, in Poland, is supposed to contain salt enough to supply the whole world for many centuries, although it has been wrought for six or seven hundred years. It has been explored to an astonishing depth ; and its subterranean regions are excavated into houses, chapels, and other ornamental forms, the roof being supported by decorated pillars of salt.
Seite 103 - ... origin. Diamonds with few exceptions are obtained from alluvial washings. In Brazil, the sands and pebbles of the diamond rivers and brooks (the waters of which are drawn off in the dry season to allow of the work) are collected and washed under a shed, by a stream of water passing through a succession of boxes. A negro washer stands by each box, and inspectors are stationed at intervals.
Seite 84 - WITH REAGENTS. In the examination of sulphides, arsenides, antimonides and related ores, the assay should be roasted before using a flux, in order to convert the substance into an oxide. This is done by spreading the substance out on a piece of charcoal and exposing it to a gentle heat in the...
Seite 327 - Peat is vegetation which has undergone, in part, the change to coal, and, in some cases, it has become brown coal. The conditions of change are somewhat different from those of the beds of good coal, since in the case of peat the air has access, while in that of the coal the air was more or less excluded by overlying strata, and the more perfect the exclusion, other things equal, the better the coal.
Seite 141 - ... Tyrol, Siberia, Thuringia, &c. In Chili it is abundant at the various mines. In Wisconsin and Missouri it is so abundant as to be worked for copper. It was formerly taken for green malachite. It also occurs at the Somerville and Schuyler's mine, NJ, at Morgantown, Penn., and Wolcotville, Conn.
Seite 137 - Ibs. is the annual consumption of blue vitriol in the United States. In some mines the solution of sulphate of copper is so abundant as to afford considerable copper, which is obtained by immersing clean iron in it. It is called Copper of Cementation. At the copper springs of Wicklow, Ireland, about 500 tons of iron were laid at one time in the pits : in about twelve...
Seite 327 - It receives a brilliant polish, and is set in jewelry. It is the Gagates of Dioscorides and Pliny, a name derived from the river Gagas, in Syria, near the mouth of which it was found, and the origin of the term jet, now in use.

Bibliografische Informationen