Report of Progress ...

Board of Commissioners for the Second Geological Survey, 1875

Τι λένε οι χρήστες - Σύνταξη κριτικής

Δεν εντοπίσαμε κριτικές στις συνήθεις τοποθεσίες.

Επιλεγμένες σελίδες

Άλλες εκδόσεις - Προβολή όλων

Συχνά εμφανιζόμενοι όροι και φράσεις

Δημοφιλή αποσπάσματα

Σελίδα 7 - Pa., near Pittsburgh. A farmer was ploughing in the field, where, seeing a snake, he seized a stone, as he supposed, to destroy the animal, but, finding it remarkably heavy, he was attracted, after completing his purpose, to examine the body which possessed such a remarkable weight. It was carried to Pittsburgh, where it was found to be very malleable, and unfortunately wrought into a bar, which has since been lost sight of. The mass was of an orvidal figure, almost six or seven inches in diameter,...
Σελίδα 3 - ... millions of dollars. And if, as is pretty certain, the corporate limits of the city would afford eight times this bulk of clay, we have more gold than has yet been brought, according to the statistics, from California and Australia.
Σελίδα 3 - Passing over the evidence respecting its presence in various galenas, in metallic lead, copper, silver, antimony, etc., we cite the following, perhaps the most curious result of all. Underneath the paved city of Philadelphia there lies a deposit of clay, whose area, by a probable estimate, would measure over three miles square, enabling us to figure out the convenient sum of ten square miles. The average depth is believed to be not less than fifteen feet. The inquiry was started whether gold was...
Σελίδα 70 - Deshong's quarry, near Leiperville ; in the granitic veins of the same quarry and in the vicinity very beautiful slender crystals of yellowish, greenish and blueish beryl have been found ; they are sometimes ten to twelve inches in length and one and a half inches in diameter, and frequently terminated with the basal plane.
Σελίδα 3 - This experiment was repeated upon clay taken from a brickyard in the suburbs of the city, with nearly the same result. In order to calculate with some accuracy the value of this body of •wealth, we cut out blocks of the clay, and found that on an average, a cubic foot, as it lies in the ground, weighs 120 pounds, as near as may be ; making the specific gravity 1 -92. The assay gives seven-tenths of a grain, say three cents' worth of gold to the cubic foot.
Σελίδα 120 - H = 1.5 ; — 2.66-2.70. The following varieties have been analyzed by Roepper: a. pale yellowish-white; 6. ochre-yellow (after having been dried during one hour at 105°C.) ; c. Blake analyzed a pale-yellow variety: abc Silicic acid — 48.94 46.45 41.36 Alumina = 10.66 7.41 8.04 Ferric oxide — 3.85 14.28 9.55 Zinc oxide = 26.95 22.86 32.24 Magnesia = ) 0.97 1.02 Lime...
Σελίδα 46 - I secured a considerable number of specimens from the "big hill" at . •Cornwall, and proved them to be a new mineral. Amorphous ; orange yellow to orange red ; forms very thin, sometimes raglike coatings upon magnetite ; soft. On heating loses water and becomes black ; contains water and cuprous oxide. It is impossible to obtain from the quantity which I have noticed, enough for analysis ; its composition is probably H, O, Cu, O.
Σελίδα 16 - No actual occurrence of chalcocite is known in Lehigh County, although it may well be found in association with malachite in Flint Hill in the extreme southeastern corner of the county. "According to a private communication from Prof. "W. Th. Roepper, of Bethlehem, chalcocite, occasionally in small crystals, is frequently met with on the line of junction between the South Mountain rocks and the Triassic sandstone, which latter is often colored green by malachite, resulting from the oxidation of the...
Σελίδα 46 - it occurs in small rhombic crystals in geodes, frequently associated with turgite in limonite beds, especially in Williams and Saucon townships, Northampton County.
Σελίδα 165 - ... a beautiful pink or rose color, and is not unlike that of peach blossoms." (Blake, 1853.) Blake published a further description in 1858 (see bibliography), JL Smith discussed it in 1854, and Genth in 1857 and 1875. Genth gives additional data with analysis as follows : "The original specimen . . . consisted of an aggregate of small orthorhombic crystals in thin four-sided plates or minute tables, with beveled edges and a micaceous cleavage ; it shows pearly lustre, and a delicate pinkish, grayish-white...

Πληροφορίες βιβλιογραφίας