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alfo alſo amygdaloidal appears bafalt beds belong Bohemia changes characters chemical clafs clay clay-flate coal colour common compofed concretions confiderable confidered connected contains covered cryftals denominated depofitions diftinct direction earth effects example extended faid fame fand fecond feet felfpar feries firft fituated flaty fmall foffils fome fometimes formation formed frequently ftill ftone ftrata ftructure fuch furface globe gneifs granite granular greater green greenftone grey Grey-wacke gypfum height hence hills hornblende important iſland Italy kind land lefs Limeſtone lower maffes matter mechanical mentioned mica mica-flate mixed moft moſt mountain group nature nearly newer neweſt obferved occurs oldeft older original particularly period places pofition Porphyry portion prefent primitive principal probably productions quantity quartz rarely relations remarkable river rocks Sandſtone Saxony Scotland thefe theſe thofe thoſe tion tranfition trap traverſe ufually valleys variety veins volcanoes whole
Page 344 - There is but one place from whence thefe minerals may have come ; this is the bowels of the earth ; the place of power and expanfion ; the place from whence has proceeded...
Page 80 - Although we cannot give a very satisfactory answer to this question, it is evident that the theory of diminution of water remains equally probable. We may be fully convinced of its truth, and are so, although we may not be able to explain it. To know from observation that a great phenomenon took place, is a very different thing from ascertaining how it happened.
Page vii - Companion of the Most Honourable Order of the Bath, Member of the Supreme Council of India. The Honourable John Peter Grant, Member of the Supreme Council of India. The Honourable Barnes Peacock, Member of the Supreme Council of India. Charles Allen, Member of the Legislative Council of India.
Page 42 - ... re-assertion of the principal Wernerian notions. We should form a very false conception of the Wernerian Geognosy, were we to believe it to have any resemblance to those monstrosities known under the name of Theories of the Earth. . . . Armed with all the facts and inferences contained in these visionary fabrics, what account would we be able to give of the mineralogy of a country, if required of us, or of the general relations of the great masses of which the globe is composed? (Jameson, 1808,...
Page 65 - Chap. IV. General account of the different formations, in regard to their succession and stratification, and this illustrated by a short description of the Hartz and Saxon Erzgebirge. Chap. V, Theory of the diminution of the waters of the globe — Description of overlying formations.
Page v - THIS volume of the System of Mineralogy is to be viewed as a Sketch of the Science of Geognosy, in its present state. It contains a statement of the best ascertained facts respecting the aspect of the Surface, and the Structure of the Crust of the Earth, and a few inferences, which appear to be legitimate, with regard to their mode of formation. It is intended also as the Text Book for my Lectures on Geognosy.
Page 150 - ... Wanlockhead ; in his Manual of Mineralogy, 1821, he says, " Greywackes and transition clay-slate abound in all the mountain ranges south of the Frith of Forth, are also frequent to the north of the same boundary, and are widely distributed in England"] of the Frith of Forth, are principally composed of this rock, and many, if not the whole, of the mountains in Cumberland, appear to be of the same nature.
Page 345 - ... fide. Thefe fucceffive coats, it is material to remark, are not in planes/ but in uneven furfaces, of which the inequalities are evidently determined by thofe of the walls, that is, of the rock which forms the fides of the vein : neither are they horizontal, but are parallel to the walls, whether thefe be perpendicular or inclined. Here, therefore, there is no appearance of the action of that ftatical law, which has directed the arrangement of the other ftrata, and which tends to make the plane...
Page 71 - Chap. V, Theory of the diminution of the waters of the globe — Description of overlying formations. — An investigation of the original contents of the waters of the globe, during the different periods of the earth's formation — The division of rocks into five classes.