A Dictionary of chemistry and the allied branches of other sciences v. 5, 1883, Volume 5

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Longmans, Green & Company, 1883
 

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Page 354 - This result gives the weight of a bulk of water equal to that of the specimen, and by dividing the weight of the specimen in air by this number, the specific gravity is obtained.
Page 558 - It is sparingly soluble in water, but mixes in all proportions with alcohol and ether. It burns with difficulty...
Page 386 - ... brilliancy. In order to find out the extent to which the intensity of the solar spectrum could be increased without impairing the distinctness of the sodium lines, I allowed the full sunlight to shine through the sodium flame, and to my astonishment I saw that the dark lines D appeared with an extraordinary degree of clearness.
Page 387 - that the same body when heated so as to become luminous must emit the precise rays which at ordinary temperatures are absorbed ; ' after which remarkable conjecture, now amply verified by experiment, he goes on to say, ' I am therefore convinced that the explanation of the dark lines in the solar spectrum embraces that of the luminous lines in the electric spectrum.
Page 7 - ... this case also, the liquid filtered hot from the precipitated oxalate of lime, deposits a magma which must be treated as in the former process. (Berlin.) The salt, when heated to 100°, gives oft" only 23-81 per cent of water, assuming a light blue colour. — It dissolves in not less than 200 parts of cold water, and in a much smaller quantity of boiling water; but the hot solution deposits nothing on cooling, till it is evaporated to a syrupy consistence. If however the solution be evaporated...
Page 388 - ... which we see in the solar spectrum ; and this supposition is rendered still less probable by the fact that these lines do not appreciably alter when the sun approaches the horizon. It does not, on the other hand, seem at all unlikely, owing to the high temperature which we must suppose the sun's atmosphere to possess, that such vapours should be present in it.
Page 393 - The colours of the stars have their origin in the chemical constitution of the atmospheres which surround them. 4. The changes in brightness of some of the variable stars are attended with changes in the lines of absorption of their spectra. 5. The phenomena of the star in Corona appear to show that in this object at least great physical changes are in operation.
Page 388 - ... should be present in it. Hence the observations of the solar spectrum appear to me to prove the presence of iron vapour in the solar atmosphere with as great a degree of certainty as we can attain in any question of natural science.
Page 240 - ... dissolves the silica either wholly or in part, especially when a large quantity of water is present, and in that case yields a jelly on evaporation. Sulphuric acid diluted with a small quantity of water, decomposes, after long digestion, nearly all the salts of silicic acid, when reduced to powder. All silicates without exception become soluble in dilute hydrochloric or nitric acid, after fusion with from 3 to 5 times their weight of hydrate of potash or soda, carbonate of potash or soda, or...
Page 386 - I obtained a tolerably bright solar spectrum, and brought a flame coloured by sodium vapour in front of the slit. I then saw the dark lines D change into bright ones. The flame of a Bunsen's lamp threw the bright sodium lines upon the solar spectrum with unexpected brilliancy. In order to find out the extent to which the intensity of the solar spectrum could be increased without...

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