Observations on the Geology of the United States of America: With Some Remarks on the Effect Produced on the Nature and Fertility of Soils, by the Decomposition of the Different Classes of Rocks; and an Application to the Fertility of Every State in the Union, in Reference to the Accompanying Geological Map : with Two Plates

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author, 1817 - 127 páginas
 

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Página 42 - Quantities of ochre, from bright yellow to dark brown, are found in abundance in this formation, in flat horizontal beds, alternating with other earths in some places, in others in...
Página v - All inquiry into the nature and properties of rocks, or the relative situation they occupy on the surface of the earth, has been much neglected. It is only since a few years that it has been thought worth the attention of either the learned or unlearned ; and even now a great proportion of both treat such investigations with contempt, as beneath their notice. Why mankind...
Página 57 - The outline of the mountains of this formation is almost a straight line, with few interruptions, bounding long parallel ridges of nearly the same height, declining gently towards the side, where the stratification dips from the horizon, and more precipitous on the opposite side, where the edge of the stratum breaks out to the day.
Página vi - ... beneath their notice. Why mankind should have so long neglected to acquire knowledge so useful to the progress of civilization — why the substances over which they have been daily stumbling, and without whose aid they could not exercise any one art or profession, should be the last to occupy their attention — is one of those problems perhaps only to be solved by an analysis of the nature and origin of the power of the few over the many.
Página 59 - Susquehannah rivers; and a large body of alum slate on Jackson's river, Virginia; many powerful veins of the sulphate of barytes cross it in different places; granular, as that near Fincastle, or slaty, as that in Buncomb county, North Carolina. Iron and lead have as yet been the principal metals found in this formation ; the lead in the form of galena, in clusters, or what the Germans call Stockwerk, as at the lead mines on New river, Wyeth county, Virginia; the iron disseminated in pyrites, hematitic...
Página 62 - Pensylvania, with some interruption, all the way to the waters of the Tombigbee, accompanied by the usual attendants, slaty clay and freestone, with vegetable impressions, &c. ; but, in no instance that I have seen or heard of, covered by, or alternating with, any rock resembling basalt ; or indeed any of those called the newest floetz trap formation.
Página 38 - ... magnetic iron ore, from eight to twelve feet thick, wrought in Franconia, near the White Hills, New Hampshire; that there is a similar bed in the direction of the stratification, six miles north-east of Philipstown on the Hudson river; and, still following the direction of the stratification, that the same ore occupies a bed nearly of the same thickness at Ringwood, Mount Pleasant, and Suckusanny, in New Jersey; losing itself, as it approaches the end of the primitive ridge, near Blackwater —...
Página 52 - ... are found. These beds are mixed, and alternate occasionally in the same gneiss, with the primitive limestone, the beds of hornblende and hornblende slate, serpentine, magnetic iron ore, and feldspar rocks. In some places this gneiss contains so much mica, as to run into mica slate; in others, large nodules of quartz or feldspar; in others, hornblende takes the place of the mica; in short, I scarcely know any of the primitive rocks that may not occasionally be found included in the gneiss formation.
Página 30 - Necessity dictates the adoption of some system so far as respects the classification and arrangement of names. The Wernerian seems to be the most suitable, first, because it is the most perfect and extensive in its general outlines; and secondly, the nature and relative situation of the minerals in the United States, whilst they are certainly the most extensive of any field yet examined, may perhaps be found the most correct elucidation of the general accuracy of that theory, so far as respects the...
Página ix - Wolfram accompanies tin in the greatest part of the tin mines; of course the appearance of walfram is a sign, that most probably tin may be found in the vicinity, &c. Great sums of money have been lost in the United States, and in other countries, by digging for substances among classes of rocks, which have never been found to contain them elsewhere; and of course the probability was against their being found in that class of rocks here. "A knowledge of the nature and properties of rocks, and the...

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