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Página 449 - ... 5. This work has conferred many valuable benefits upon science, indirectly and incidentally, in the invention or perfection of instruments, in the improvement of methods of observation or of computation, in the development which it has given to special subjects of interesting inquiry, and in the stimulus which it has furnished to the scientific talent of the country, especially in the field of astronomical observation and investigation. 6. A careful study of the progress made from year to year,...
Página 51 - The Principia will ever remain a monument of the profound genius which revealed to us the greatest law of the universe,"* are the words of Laplace. " That work stands pre-eminent above all the other productions of the human mind. -(- " The discovery of that simple and general law by the greatness and the variety of the objects which it embraces confers honour upon the intellect of man.
Página 233 - Description of nine new species of Crinoidea from the Subcarboniferous rocks of Indiana and Kentucky, Am.
Página 13 - ... besides some nearly mature foetuses contained in the mouth, two or three were squeezed apparently from the stomach; but not bearing any marks of violence, or of the action of the gastric fluid. It is probable that these found their way into that last cavity after death, in consequence of the relaxation of the sphincter which separates the cavities of the mouth and the stomach.
Página 195 - Agassiz maintains, substantially, that each species originated where it now occurs, probably in as great a number of individuals occupying as large an area, and generally the same area, or the same discontinuous areas, as at the present time.
Página 147 - Sir Humphry Davy gave me the analysis to make as a first attempt in chemistry, at a time when my fear was greater than my confidence, and both far greater than my knowledge ; at a time, also, when I had no thought of ever writing an original paper on science.
Página 105 - Wherever there has been a variation from the usual conditions of the soil, on the prairie or in the river bottom, there is a corresponding change in the character of the vegetation. Thus, on the prairies we sometimes meet with ridges of coarse material, apparently deposits of drift, on which, from some local cause, there has never been an accumulation of fine sediment; in such localities we invariably find a growth of timber. This is the origin of the groves scattered over the prairies, for whose...
Página 294 - ... expect to find near by those products of the chemical changes effected in the coal. Such is the delicacy of the balance existing between the elements of the heavy hydrocarbons, that no second distillation of them can be effected; they always undergo decomposition by heat, with the separation of carbon, which, under any known natural conditions, would remain to attest their previous presence. Considerations of this kind have led me to experiment on the changes which coals undergo by heat, where...
Página 424 - Hobson, RN, Captain Allen Young, and myself. As a somewhat detailed report of our proceedings will doubtless be interesting to their Lordships, it is herewith enclosed, together with a chart of our discoveries and explorations, and at the earliest opportunity I will present myself at the Admiralty to afford further information, and lay before their Lordships the record found at Port Victory. I have, &c., FL M'CLINTOCK, Captain, RN To the Secretary of the Admiralty, London.