. An introduction to geology : intended to convey a practical knowledge of the science, and comprising the most important recent discoveries, with explanations of the facts and phenomena which serve to confirm or invalidate various geological theories. sian limestone of Bredon and Clouds Hill than may appearconsistent with an introductory work, is, that the strata of the latterhill present an anomalous appearance, which I have not observedelsewhere, and which is connected with the enquiry respecting thecharacter of stratified rocks. At Clouds Hill, the face of the rockwhich is worked, rises to
. An introduction to geology : intended to convey a practical knowledge of the science, and comprising the most important recent discoveries, with explanations of the facts and phenomena which serve to confirm or invalidate various geological theories. sian limestone of Bredon and Clouds Hill than may appearconsistent with an introductory work, is, that the strata of the latterhill present an anomalous appearance, which I have not observedelsewhere, and which is connected with the enquiry respecting thecharacter of stratified rocks. At Clouds Hill, the face of the rockwhich is worked, rises to the height of about 300 feet. The strati-fication is most distinctly marked by regular strata seams, or partings,which show the elevation of the strata to be about 60^. In themidst of these strata there are masses in which all traces of stratifi-cation are obliterated ; these masses are not separated by any part-ings or divisions whatever from the strata which surround them; themasses and strata are precisely of the same quality, and similar inappearance. The masses are more difficult to work because theyhave no regular partings; these masses are, on this account, called,by the quarrymen, knobs. The annexed cut represents one of thesemasses—. a a, strata of limestone; J, an unstratified knob. Instances of unstratified beds and masses of one kind of rock, in-terposed between regular strata of another kind, are not uncommon;and in the midst of primary rocks, divided by regular cleavages, partsmay be frequently seen, in which the cleavages or divisions are ob-literated ; but, in both these cases, the solution of the cause of thisobhteration may be found in igneous fusion, combined with refrigera- 02 MOUNTAIN LIMESTONE. tion. If the unstratified masses at Clouds Hill owe their form to theaction of heat, it is difficult, if not impossible, to conceive how thisheat could have changed internal portions of the limestone, withoutaffecting the surrounding strata. In Devonshire, and el
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Keywords: ., bookcentury1800, bookidintroduc, booksubjectgeology, bookyear1833
