. The pictorial sketch-book of Pennsylvania, or, Its scenery, internal improvements, resources, and agriculture, populary described . Fit!. .7. lying in an uncouforuiable positiiu to tlio more modern overlayingsuriaoe. Various writers have eautioned tlie observer against eertain decep-tive appearances of the strata in particular linos of coast, (Avhich areno less frequent in our mountain regions,) Avhcre beds, apparentlyhorizont:^, in reality dip at a very considerable angle. The follow-ing tig. 3S, exhibits a headland as seen from the south, in whichthe strata appear to the eye perfectly leve
. The pictorial sketch-book of Pennsylvania, or, Its scenery, internal improvements, resources, and agriculture, populary described . Fit!. .7. lying in an uncouforuiable positiiu to tlio more modern overlayingsuriaoe. Various writers have eautioned tlie observer against eertain decep-tive appearances of the strata in particular linos of coast, (Avhich areno less frequent in our mountain regions,) Avhcre beds, apparentlyhorizont:^, in reality dip at a very considerable angle. The follow-ing tig. 3S, exhibits a headland as seen from the south, in whichthe strata appear to the eye perfectly level. There appears to be nomistake about their horizontal position ; but if the headland treads. FIG. 3S. off, at the point j), in fig. 30, to the northward, aflording a view ofthe cliffs westward, it will be seen that the appearance from thesouth is defective, for the lines here show a considerable angle to thenorth, and gradually increasing in their dip, finally become verticalat a. It has already been intimated that fossiliferous rocks follow aninvariable order of succession, but that the arranc-ement. althou-linever reversed, is sometimes imperfect; so that, whikMve never meetb going before a, or c preceding />, yet we occasionally miss not onlya single letter, but a succession of letters, and find, in certain locali- A N T ir II A (J I T P) C O A L FORMATION. 151
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Keywords: ., bookcentury1800, bookdecade, booksubjectminesandmineralresources
