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accessions American Batchen beds biotite biotite granite birds blocks brown building stone Carboniferous catalogue Charles City Coarse collection compact containing crystalline cube curator dark gray Department Devonian diabase District of Columbia dolomite durable examination exchange exhibition feet feldspar fossiliferous fossils fragments Geographical Exploring Commission gneiss grained grammes granite green greenish Hall hornblende inches insects iron Island John light colored light gray limestone localities Lower Silurian mammals Marble Company material Medium Mexican Geographical Exploring Mexico mica minerals mottled nearly black North occurs Ohio oolitic Orleans Exposition ornamental Pennsylvania pink polished porphyry present Prof Province quarry quartz Railroad received rock Rutland County sandstone serpentine shells skins slab slate species specimens Sub-Carboniferous surface Tenth Census tion Triassic U. S. Fish Commission U. S. Geological Survey U. S. National Museum Upper Silurian variety veined Virginia Washington County West Rutland William York
Seite 457 - Counties. At Amherst the quarries are located in a series of ledges which were once the shore cliffs of Lake Erie. The elevated position of the stones is a great advantage, since the light and uniform color seems due to the fact that this elevation produces a free drainage, and the stones have been traversed by atmospheric waters to such 'a degree that all processes of oxidation which are possible have been very nearly completed. The stone here as elsewhere varies considerably in character and solidity...
Seite 336 - It should not be forgotten, however, that any stone giving root to lichens is not one of those which most easily disintegrates, for in these the destruction goes on so rapidly that the surface does not allow the growth of such plants. The lichen-covered rocks in nature are usually those of great strength and durability. None of the softer or rapidly decaying rocks produce this vegetation.
Seite 329 - SAND BLAST. As already noted, the sand blast has been utilized to some extent in the work of lettering head-stones, and for producing delicate tracings on the Sioux Falls quartzite. That the process is still so little used is due, as I am informed, to the opposition of trades-unions, and not to any deficiency of adaptability in the process itself. (8) HAND IMPLEMENTS. Face Hammer. — This is a heavy square-faced hammer, weighing from 15 to 25 pounds, and used for roughly shaping the blocks as they...
Seite 458 - Nearly all of the quarries exhibit this diversity of material, although the order of arrangement is not always the same. The colors are light buff and bluish gray, the buff stone occurring above the line of perfect drainage and extending down as far as the 2 feet of bridge stone, forming a total thickness of 27 feet. In most of the Amherst quarries the relative amount of buff stone is greater. Difference in color and texture has given rise to various local names which may be mentioned here. The colors...
Seite 366 - The color of this last is dark, and the quantity of the talc is considerably large. A large bed occurs in connection with soapstone on the north side of Deerfield River, in Zoar, near the turnpike from Greenfield to Williamstown. Specimens from this place resemble those from the celebrated localities of this rock at Zoblitz, in Saxony.
Seite 334 - The injurious effects of artificial heat, such as is produced by a burning building, are, of course, greater in proportion as the temperature is higher. Unfortunately sufficient and reliable data are not at hand for estimating accurately the comparative enduring powers of various stones under these trying circumstances. It seems, however, to be well proven that of all stones granite is the least fire-proof, while the fact that certain of the finegrained siliceous sandstones are used for furnace backings...
Seite 324 - The machine is placed upoii a platform on trucks arranged to run upon a track. When adjusted for work it may be braced by the pointed legs shown. The boring apparatus is attached by a swivel to a perpendicular guide-bar. This guide-bar is secured to the boiler behind it, which forms the main support of the machine. Upon the guide-bar the boring apparatus may...
Seite 5 - That, in proportion as suitable arrangements can be made for their reception, all objects of art and of foreign and curious research, and all objects of natural history, plants, and geological and mineralogical specimens, belonging or hereafter to belong, to the United States...
Seite 72 - Assistant Secretary of the Smithsonian Institution, in charge of the US National Museum.
Seite 360 - Liberty; also one about two and a half miles westward of New London. Continuing in the same direction it is seen at the meadows of Goose Creek, where it has been quarried to some extent. Continuing in the same general direction the soapstone again appears in several nearly parallel ranges, of which the most eastern makes its appearance near the Pigg River, in Franklin County, A second belt occurs in the same vicinity near the eastern base of Jack's Mountain ; a third still farther west, about one...