Bulletin of the American Museum of Natural History Volume 1 - Softcover

History, American Museum Of Natural

Softcover

ISBN 10: 1231072261 ISBN 13: 9781231072264

Verlag: RareBooksClub.com, 2012

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1886 Excerpt: ...as Mt. Ascutney and Little Ascutney. The igneous rock seems to have been erupted from below through one or more vents and spread over the rock adjacent, very much in the manner of modern lava. The importance of these facts leads us to give them more in detail than usual. All the varieties of rocks occurring upon the mountains are well represented in the Museum. The summit of Ascutney lies near the southeast corner of Windsor; but portions of the mass are situated in the towns of West Windsor and Weathersfield. If the two mountains were just alike, the granitic area, when protracted upon a map, would resemble a pair of spectacles; as it is, the eastern higher area is four and one-half miles long, two and one-eighth wide, and the summit 3186 feet above sea level, while the base of the cone is 1200 feet above the sea. The western area is nearly circular, one and one-fourth miles in diameter, and the apex 1700 feet above the sea. The rock is often a hornblende granite--mica not being excluded--and the variety called gram tell by Dr. Hawes, containing neither of the accessory minerals, is abundant in irregular patches in every part of the cones. Brecciated masses composed of the underlying stratified rocks are plentiful upon the west side of the larger mass and upon the smaller mountain; insomuch that one can easily believe portions of the granite have been made from the melting down of the fragments. The major axis of the "spectacles" is six and one-half miles long, at right angles to the course of the strata. Two stratified groups underlie the unstratified area. Most of the eastern cone is located upon the calciferous mica schist. The rest of it, and the smaller cone, lies upon gneiss. The gneiss underlies the mica schists at the same angle of dip, a...

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• Verlag: RareBooksClub.com
• Erscheinungsdatum: 2012
• ISBN 10: 1231072261
• ISBN 13: 9781231072264
• Einband: Tapa blanda
• Anzahl der Seiten: 126