Report of the State Geologist on the Mineral Industries and Geology of Certain Areas of Vermont, Volume 8 |
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Albany amphibolite anticlinal Barre basin beds belt of slate Black River C. H. Hitchcock C. H. Richardson Cambrian Champlain Valley channels Chazy clays cleavage conglomerate Connecticut Conway group County Craftsbury Curve deposits Devonian diabase dikes east eastern extends feet fossils G. H. Perkins Geologist Geology of Vermont gneiss Goshen Grand Isle granite graptolites Green Mountains green schists Hill Hudson igneous inches intrusives Irasburg Isle La Motte Lake Champlain Lake Memphremagog ledges limestone locality Lower Cambrian marble mass material Memphremagog mica schist miles Montpelier northern Norwich Ordovician outcrops pebbles phyllite Plate Pleistocene present Professor quarries quartz quartzite region ridge rill-channels rocks Rutland schists sericite sericite schist shale shows side Sixth Report specimens staurolite stone strata surface synclinal terranes tests Thetford thickness thru town township veins village voltage Waits River Waits River limestone western
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Page 43 - ... now, and the lower part of its extent has become covered by the present lake. From the time of the union of Lakes Iroquois and Hudson-Champlain...
Page 43 - ... about 50 feet, joined the broad expanse of water in the Ontario basin with the larger expanse in the St. Lawrence and Ottawa valleys and the basin of Lake Champlain. At the subsequent time of ingress of the sea past Quebec the level of Lake St. Lawrence fell probably 50 feet or less to the ocean level. The place of the glacial lake so far westward as the Thousand Islands was then taken by the sea, with the marine fauna which is preserved in the Leda clays and Saxicava sands.
Page 200 - One of the most remarkable slate belts of this country lies in eastern New York and western Vermont, between the Taconic range on the east and Lake Champlain and the Hudson on the west, and chiefly between the Hoosic River on the south and the towns of Benson and Hubbardton, in Vermont, on the north. It attains a maximum length of 68 miles and an average width of about seven miles. The great producing centres lie in Washington County, NY, and Rutland, Vt. The slates in this field are green of various...
Page 201 - ... square being a sufficient number of pieces of slate of any size to cover 100 square feet of roof, with allowance generally for a 3-inch lap. The size of the pieces of slate making up a square ranges from 7 by 9 inches to 16 by 24 inches, and the number of pieces in a square ranges from 85 to 686, according to the size of the pieces. The ordinary thickness of a piece is from one-eighth to three-sixteenths of an inch, and the approximate weight per square is about 650 pounds. The slate is generally...
Page 209 - ... amount of disintegration through freezing. Density tests are of value, since the greater the specific gravity of one of several similar substances, the greater is its strength. Hardness may or may not be a desirable quality, accordingly as it is related to density or to brittleness. Lastly a test for corrodibility, or the capacity of being disintegrated by the chemical action of smoke and of fumes from manufactories, is desirable. (1) STRENGTH AND TOUGHNESS.
Page 201 - squares," a square being a sufficient number of pieces of slate of any size to cover 100 square feet of roof, with allowance generally for a 3-inch lap. The size of the pieces of slate making up a square ranges from 7 by 9 inches to 16 by 24 inches...
Page 85 - We have found striking examples where the pebbles of conglomerates have been elongated and flattened so as at length to be converted into the silicious lamince of the schists and gneiss and the cement into mica, tak, and feldspar.
Page 45 - Kdward district, found the Hudson from Fort Edward southward a much more powerful river than it is now. During the development of Lake Vermont and as soon as the ice had withdrawn from the northern slope of the Adirondacks to the very border of tha>t district, a powerful discharge of water coursed along the ice front from the St Lawrence valley to the eastward and fell into the lake near West Chazy. The course of this torrent is marked by the so called " flat rock " areas from Covey hill southward...
Page 50 - ... ice front of their time partly conceals the full history of the disappearance of the ice from the immediate vicinity of the gorge. As soon as the Mohawk valley was opened a large contribution of water charged with fine sediment came into the Hudson valley from that direction and for some time later was distributed far and wide to the south in the form of clays which may be traced as an almost continuous sheet over the rock benches and in the gorge itself as far south at least as Saugerties. The...
Page 89 - No. 8. Phylogeny of the Pelecypoda; the Aviculidae and their allies. By Robert Tracy Jackson.