Topographic and Geological Survey of Pennsylvania, Ausgabe 91913 |
Andere Ausgaben - Alle anzeigen
Häufige Begriffe und Wortgruppen
A. S. McCreath acid Allegheny Alumina analyses anthracite Beaver Berks county Blair brick Bucks Cambrian cent character chemical Chester county Clearfield Clearfield county coke color composition copper corundum Creek crystals Delaware county deposits district dolomite east Ehrenfeld Fayette feet feldspar fire clay Fixed carbon flint clay formation Freeport coal fuel ratio furnace garnet Geological Survey grade granite graphite green H₂O hematite Huntingdon county Insoluble residue K₂O kaolin kaolinite Kittanning known Lancaster county Lehigh Lehigh county lime limestone limonite localities magnesia magnesium manganese manufacture marble material metallic mica miles mineral paints mines Monongahela Montgomery nickel occurs ocher Oxide of iron Pennsylvania percentage Philadelphia Phosphorus pigment Pittsburgh coal potash present produced quantity quarry quartz refractory reported river sand sandstone schists serpentine Sesquioxide shales Siderite silica SiO2 slate South Mountain stone Sulphur thickness township U. S. Geol Valley Volatile West yellow zinc
Beliebte Passagen
Seite 24 - If there be low per percentage of iron present and a higher percentage of lime (about three times the iron), the clay product will burn buff. If the high percentage of lime be due to lumps of lime carbonate, the brick on burning will crack and warp. Very high percentages of lime are apt to ruin the clay. It is not always possible to predict the color of the burned ware from the color of the clay. Red clays will usually burn red, blue clays may burn red or buff. Dark or black clays are usually high...
Seite 101 - For this purpose no mica is as satisfactory as the phlogopite or "amber" mica. This mica is of about the same hardness as the copper of the commutator segments, and therefore wears down evenly without causing the machine to spark. A large quantity of the sheet mica used in electrical apparatus is built up into "micanite...
Seite 84 - ... and which will slake by themselves when placed in water. They gradually harden under water. 5. Natural cement or roman cement. Made from limestones, either high-calcium or dolomitic, which contain from ten to thirty per cent, of sandy and clayey matter; and which will not slake, without first being finely ground. They harden under water much more rapidly, and to a harder final product, than hydraulic lime.
Seite 91 - County, containing the villages of Egypt, Coplay, Northampton, Whitehall, and Siegfried. The cement plants which were located here at an early date secured control of most of the cement-rock deposits in the vicinity, and plants of later establishment have therefore been forced to locate farther and farther away from the original center of the district. At present the district includes parts of Berks, Lehigh, and Northampton counties, Pa., and Warren County, NJ, reaching from near Reading, Pa., at...
Seite 84 - This term is applied to the finely pulverized product resulting from the calcination to incipient fusion of an intimate mixture of properly proportioned argillaceous and calcareous materials, and to which no addition greater than 3 per cent, has been made subsequent to calcination.
Seite 110 - In a number of places these shales have been utilized in the manufacture of paint, and when ground fine and mixed with oil they are very serviceable. Their principal use, however, is in the manufacture of oilcloth and linoleum. They are considerably lighter in color than the ochers and contain a much lower percentage of hydrous iron oxide, as a rule not more than 5 per cent.
Seite 59 - PENNSYLVANIA.—The serpentine belt that comes diagonally across Maryland, is continued through the counties of Lancaster, Chester, Delaware, Montgomery and Bucks. Corundum is found associated with it in many places, especially in Chester and Delaware counties, and, a few years ago, was mined to a certain extent in the former. It is found here in chloritic zones about the serpentine, but in larger amounts in granular albite, much like the occurrence in feldspar veins at Buck creek, in Clay county,...
Seite 92 - Throughout most of the Lehigh district the practice is to mix with a relatively large amount of the "cement rock" or argillaceous limestone a small amount of pure limestone, in order to bring the lime carbonate content up to the percentage proper for a Portland-cement mixture. As above noted, all of the "cement rock...
Seite 75 - COMPOSITION OF THE ORES. The iron content of these ores is extremely variable, but as the ore is mined probably averages not far from 45 per cent. Rather constant chemical characteristics are low phosphorus, high sulphur, silica, lime, and magnesia, and the presence of copper. Small amounts of cobalt have been found in ores from Cornwall and Dillsburg.
Seite 89 - Pittsburgh Limestone. This limestone underlies the Pittsburgh coal at an interval of about twenty feet. It has a wide range throughout south-western Pennsylvania, and extends eastward across the Allegheny Mountain into the Cumberland basin of Maryland, showing also in the Salisbury basin in Somerset county. The following are two analyses of this limestone : Indiana County.