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Agassiz Alpine Alps animals antennae appearance beds boulders Bude light cause cells centre chain Charpentier chyle coal composed considerable crust Crustacea deposits depth diluvial diluvium direction distance earth edge Edinburgh elevated epoch erratic blocks exist extended extremity fact feet fibres flanks flysch formation fossils gauge genus geological germinal spot germinal vesicle glacial theory glacier gneiss granite Greenockite heat height Ichthyosaurus improvements inches interior joint Jura lacteals lake light limestone Loch Treig lower mass matter means melting membrane Milky moraines motion mountains nature nebula nucleus observed oolitic organic oviduct ovum period phenomena phenomenon Plate Plesiosaur polished portion present produced rain regions remarkable reptiles rocks rounded seen shew side snow Society species spines stars steam strata structure suppose surface temperature terminal thickness thoracic segment tion Valais valleys vertebrae villus walls whole winter
Strona 289 - Engineers. 1 propose, therefore, to show how these extraordinary and most important changes occur, and shall point out some, at least, of the modes by which we can demonstrate the truth of this assertion by actual experiment. The principal causes which produce this change are percussion, heat, and magnetism; and it is doubtful whether either of these means per...
Strona 91 - He next happily devised a method of obtaining from ordinary coal gas, purified in a simple apparatus of his own, and burned with oxygen derived from the atmosphere, an effulgence adequate to every purpose of internal and external illumination, which is now used in the House of Commons with perfect success, and at a cost of only twelve shillings per night, whereas that of the candles, previously used there, amounted to six pounds, eleven shillings, per night. This new Bude light possesses the following...
Strona 292 - Dr Wollaston first pointed out that the forms in which native iron is disposed to break, are those of the regular octahedron and tetrahedron, or rhomboid, consisting of these forms combined. The tough and fibrous character of wrought iron is entirely produced by art; and we see in these changes that have been described, an effort at returning to the natural and primal form; the crystalline...
Strona 294 - If this slloy is plunged into cold water, and quickly withdrawn and taken in the hand, it becomes sufficiently hot, after a few moments, to burn the fingers. The cause of this phenomenon is, that during the solidification and crystallization of the internal parts, the latent heat of these is set free, and communicates itself to the surface before the fixing and cooling." The alteration in the internal arrangement of the particles, as proved by the surfaces of fracture, is not however noticed, and...
Strona 292 - ... wrought iron is entirely produced by art; and we see in these changes that have been described, an effort at returning to the natural and primal form; the crystalline structure, in fact, being the natural state of a large number of the metals ; and Sir Humphrey Davy has shewn that all those which are fusible by ordinary means assume the form of regular crystals by slow cooling.
Strona 82 - But where is the trace of such mammalia in the strata immediately succeeding those in which we lose sight of the relics of the great Dinosaurian Reptiles ? Or where, indeed, can any mammiferous animal be pointed out whose organization can by any ingenuity or licence of conjecture, be derived without violation of all known anatomical and physiological principles, from transmutation or progressive development of the highest reptiles ? If something more than a slight inspection be bestowed upon the...
Strona 207 - Bailey has brought to light the interesting fact, that a large portion of the calcareous rock defined by Prof. HD Rogers as the third formation of the upper secondary, is made up, at the localities where he examined it, of great quantities of microscopic shells belonging to the foraminifera of D'Orbigny, which order includes those multilocular shells which compose a large part of the calcareous sands, &c. of Grignon and other localities in the tertiary deposits of Europe. Since the minute multilocular...
Strona 91 - Argand flame, while, by means of an accurate gas metre, the former was ascertained to consume only 4.4 times the quantity of gas consumed by the latter, demonstrating the economy of the Bude light over common gas to be greater than two to one; and this economy increases in proportion to the magnitude of the light.
Strona 290 - ... of the iron. It is not difficult to produce the same effects by repeated blows from a hand-hammer on small bars of iron; but it appears to depend upon something peculiar in the blow, which, to produce the effect, must occasion a complete vibration among the particles in the neighborhood of the part which is struck. And it is remarkable that the effects of the blows, in all cases, seem to be confined within certain limited distances of the spot which receives the strokes. Mr. Charles Manby has...
Strona 350 - ... exterior, but not discoloured. I may observe, in passing, that the fissures which, in the lower part and near the sides of glaciers, form the granules, about which so much has been written, are stopped by the independent formation of the veins in the ice, which thus demonstrate their prior origin. " One afternoon I happened to ascend higher than usual above the level of the Mer de Glace, and was struck by the appearance of discoloured bands traversing its surface nearly in the form indicated...