Principles of Geology: Being an Inquiry how for the Former Changes of the Earth's Surface are Referrable to Causes Now in Operation, Volum 2


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Pāgina 403 - The intermixture of distinct species is guarded against by the aversion of the individuals composing them to sexual union, or by the sterility of the mule offspring. It does not appear that true hybrid races have ever been perpetuated for several generations, even by the assistance of man; for the cases usually cited relate to the crossing of mules with individuals of pure species, and not to the intermixture of hybrid with hybrid. 6thly. From the above considerations, it appears that species have...
Pāgina 372 - ... inches. It was found that the greyhounds could not support the fatigues of a long chase in this attenuated atmosphere, and before they could come up with their prey, they lay down gasping for breath ; but these same animals have produced whelps which have grown up, and are not in the least degree incommoded by the want of density in the air, but run down the hares with as much ease as the fleetest of their race in this country.
Pāgina 272 - Thy waters wasted them while they were free, And many a tyrant since ; their shores obey The stranger, slave, or savage ; their decay Has dried up realms to deserts : — not so thou, Unchangeable save to thy wild waves' play — Time writes no wrinkle on thy azure brow — Such as creation's dawn beheld, thou rollest now.
Pāgina 84 - The lava, at a small distance from its source, acquires a darker tint upon its surface, is less easily acted upon, and, as the stream widens, the surface, having lost its state of perfect solution, grows harder and harder, and cracks into innumerable fragments of very porous matter, to which they give the name of scoriae, and the appearance of which has led many to suppose that it proceeded thus from the mountain. There is, however, no truth in this. All lava, at its first exit from its native volcano,...
Pāgina 190 - They described the undulation of the earth as resembling waves, increasing in elevation as they advanced, and when they had attained a -certain fearful height, the earth would burst, and vast volumes of water, and sand, and pit-coal were discharged, as high as the tops of the trees.
Pāgina 69 - ... stature, resembling giants, appeared, sometimes on the mountain, and sometimes in the environs — that stones and smoke were thrown out, the sun was hidden, and then the giants seemed to rise again, while the sounds of trumpets were heard, &c. &c. ; and finally,' he relates, ' two entire cities, Herculaneum and Pompeii, were buried under showers of ashes, while all the people were sitting in the theatre.
Pāgina 420 - The thorny spray is torn off, and fixes itself in his hairy coat, until brushed off again in other thickets and copses. Even on the spot where the victim is devoured many of the seeds which he had swallowed immediately before the chase may be left on the ground uninjured, and ready to spring up in a new soil.
Pāgina 348 - Blumenbach judiciously observes, "that no general rule can be laid down for determining the distinctness of species, as there is no particular class of characters which can serve as a criterion.
Pāgina 77 - The crater was five miles in circumference, and about a thousand paces deep ; its sides were covered with brushwood, and at the bottom there was a plain on which cattle grazed. In the woody parts, wild boars frequently harboured. In one part of the plain, covered with ashes, were three small pools, one filled with hot and bitter water, another salter than the sea, and a third hot, but tasteless.
Pāgina 11 - Calcutta it sometimes occasions an instantaneous rise of five feet ; and both here, and in every other part of its track, the boats, on its approach, immediately quit the shore, and make for safety to the middle of the river. In the channels, between...

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