Memoirs of the Museum of Comparative Zool Ogy at Harvard College Volume 11
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1884 edition. Excerpt: ...1S79, xix. 1U3-403. bodies--especially concerning the strange lines in the sun's spectrum--it would appear that meteorites ought to be studied more critically than ever for the rarer elements, as well as for some at present unknown. Careful examinations ought also to be made on microscopic sections of recently fallen meteorites, in order to ascertain if any changes have taken place in the rock since it was first formed, but before it reached this earth, since all changes now seen in them are referred to the action of our atmosphere after the fall of the meteorite. It is not to be expected that in any way can any clue be obtained as to how recently or how long ago the meteorite left its parent mass, since no alteration in its substance can be expected to have taken place in inter-solar space. Mr. H. C. Sorby's view that it is impossible for minerals of so diverse specific gravity as iron and olivine to crystallize together in the pallasites and other metallic meteorites on the surface of the earth or any large body, but that they came from the metallic centre of small bodies, or else formed small planets by themselves, does not seem to be well founded. The same method of reasoning would prove that magnetite could not be formed with leucite, or feldspar, or augite in any lava-flow on the earth's surface; yet they are minerals of common occurrence together in lavas. Hence it is claimed here that the crystallization of silicates with metallic iron might, so far as gravity is concerned, take place on the surface of the earth as it has been proved to have done in Greenland. So too, if such a structure and arrangement of iron and olivine could not take place on the surface of a body like the earth, then the rocks of Cumberland, Rhode Island, and...
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