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alcohol alkaline alloy alumina ammonia aniline appears arsenic atmosphere Aurora axis beds boiling Breslau carbonate Carboniferous chemical chlorhydric acid chlorid clouds coal comet compound conglomerate containing copper Cretaceous crystalline crystals deposits described dissolved distance earth experiments fauna feet flask flora formation fossils genera genus geological give glass gneiss Gottingen green heat hydrogen inch iron Jour Journal less light lime limestone liquid magnetic mass metallic meteor meteorite miles mineral motion mountains nearly nitrate nucleus observations obtained oxyd paper particles pebbles phosphoric acid picrate picric acid plants plates portion potash precipitate present produced Prof quantity quartz Ramsgate remarkable Report River rocks salt sandstone schists seen Sept shales side silicate Silurian soda soil soluble solution species specimens stone strata substance sulphate sulphuric acid surface thickness tion trilobites waterglass yellow zinc
Pàgina 8 - ... that the ratio of the sines of the angles of incidence and refraction is constant for refraction in the same medium, was effected by Snell and Descartes.
Pàgina iv - A century of ferns ; being figures with brief descriptions of one hundred new or rare, or imperfectly known species of ferns', from various parts of the world. A selection from the author's "Icones plantarum,
Pàgina 152 - ... physics and upon ingenious and well-directed original experiments, this theory drew general attention to itself, especially in the United States. A memoir submitted anonymously to the American Philosophical Society of Philadelphia gained for Mr, Espy the award of the Magellanic premium in the year 1836, after a discussion remarkable for ingenuity and closeness in its progress, and for the almost unanimity of its result.
Pàgina 256 - The suddenness of the apparition of the comet in northern latitudes was one of the most impressive of its characteristics. On the 2d of July, after the twilight had disappeared, the head, to the naked eye, was much brighter than a star of the first magnitude, if only the effective impression be taken into account, although, as to intensity, it was far inferior to a Lyrae, or even to a Ursae Majoris. I should describe the head as nearly equal in brightness to that of the great comet of 1858...
Pàgina 396 - ... extensive beds of iron ore, hundreds of feet thick, which abound in that ancient system, correspond not only to great volumes of strata deprived of that metal, but, as we may suppose, to organic matters, which but for the then great diffusion of...
Pàgina 257 - On further scrutiny with the aid of an opera-glass, two sharply cut and very narrow dark channels, bounding the principal ray, could be traced for ten or fifteen degrees from the nucleus ; while outside of them, on either side, were two additional faint rays. The whole issue of nebulous matter from the nucleus far into the tail was curiously grooved and striated. It was noticed that both the principal ray and the dark channels penetrated within the outline of the curved tail, the latter being clearly...
Pàgina 402 - is no other than the Taconic system of Emmons;' which is thus, by these authors, as well as Mr. James Hall, shown to be the natural base of...
Pàgina 12 - there is good reason to believe that the limit of perfection (in the objective) has now been nearly reached, since everything which seems theoretically possible has been actually accomplished.