The Observatory, Volumen2Editors of the Observatory, 1879 "A review of astronomy" (varies). |
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Admiral Smyth angle aperture appeared Astronomer Royal atmosphere axis binary binary stars bright lines Capt Catalogue centre Christie chromosphere colour comet corona corrections crater curve dark lines deduced determined diameter disk distance double stars drawings Earth eclipse elements equations equatoreal eyepiece faint Flammarion Gill give Greenwich heliometer Herschel Hyginus inches instrument July Jupiter large number light limb lunar magnitude Mars mean measures meteors method micrometer Moon Moon's nebulæ Neison night object object-glass observations Observatory obtained orbit paper parallax period Perseids photographs planet polarization position position-angles prisms Prof proper motion radiant Ranyard refractor remarkable right ascension ring satellite Saturn seen Sept shower Society Solar Eclipse spectra spectroscope spot Struve sun-spots Sun's telescope tion Transit of Mercury Transit of Venus Venus visible
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Página 354 - The observations also show the curious connection that, at the time when the hydrogen lines were most brilliant in the corona, the calcium lines were not detected ; next, when the hydrogen lines, being still brilliant, the h line was not present (a condition of things which, in all probability, indicated a reduction of temperature), calcium began to make itself unmistakably visible) ; and finally, when the hydrogen lines are absent, H and K become striking objects in the spectrum of the corona.
Página 62 - For this purpose a piece of combustion tubing had one end drawn ont and the end turned up sharply, and sealed off (like an ill-made combustion tube of the usual form) so as to produce an approximately plane face at the end of the tube ; a small bulb was then blown at about an inch from the end, and the tube drawn out at about an inch from the bulb on the other side, so as to form a long narrower tube. Some dry rubidium or caesium chloride was next introduced into the bulb, and a fragment of fresh...
Página 96 - After further examination and consideration, the result for parallax has been increased to 8"' 82 or 8"'83. The results from photography have disappointed me much. The failure has arisen, perhaps sometimes from irregularity of limb, or from atmospheric distortion, but more frequently from faintness and from want of clear definition. Many photographs, which to the eye appeared good, lost all strength and sharpness when placed under the measuring microscope.
Página 196 - The general conclusion that follows from these results is that on this occasion we have ascertained the true nature of the corona, viz: it shines by light reflected from the sun by a cloud of meteors surrounding that luminary, and that on former occasions it has been infiltrated with materials thrown up from the chromosphere, notably with the 1474 matter and hydrogen. As the chromosphere is now quiescent this infiltration has taken place to a scarcely perceptible degree recently. This explanation...
Página 25 - Experiments with sodium, carried out in the way we have described, exhibit the following succession of appearances, as the amount of vapour is gradually diminished, commencing from the appearance when the tube is full of the vapour of sodium, part of it condensing in the cooler portion of the tube, and some being carried out by the slow current of hydrogen. During this stage, although the lower part of the tube is at a white heat...
Página 394 - The Admiralty Manual of Scientific Inquiry, prepared for the use of Officers, and Travellers in General. Map. Post 8vo, 3s.
Página 65 - ... the polarimeter, under the idea that if the precise position of elongation from the sun where the polarization of a point of the lunar surface attains a maximum could be accurately determined, it might be possible to obtain an approximate value of the refractive index of the material composing that surface, and so to distinguish between material of a vitreous nature, ejected from volcanoes, and a surface of ice and snow. The subject has been invested with the greater interest from the fact that...
Página 19 - Carinae, containing two images each of 1 85 stars, and that of Eta Argus, or Eta Carinae, as we now call it, containing 180. I think there can be no reasonable doubt that many of the stars there depicted are quite as faint as the ninth magnitude; and I have the satisfaction of adding that upon other...
Página 25 - Red light next appears, and between the red and green light is an enormous extension of the D absorption line, while a still broader dark space intervenes between the green and the blue light. The dark line in the green (wave-length about 5510) now becomes more sharply defined.
Página 19 - ... have already secured measurable photographic impressions of not less than eighty-four celestial objects, of which nineteen are double stars, and the remainder clusters ; so that, even should the undertaking remain paralyzed in its present state, the results may be regarded as richly worth the labor, money, and perhaps even the other sacrifices, that they have cost. I may add that the planets Jupiter, Mars and Saturn have likewise been photographed with sufficient distinctness to show clearly...