A Treatise on Chemistry: v. 1-3

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Page 468 - The strontia flame exhibits a great number of red rays well separated from each other by dark intervals, not to mention an orange and a very definite bright blue ray. The lithia exhibits one single red ray.
Page 498 - ... 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 66 - And as when armourers temper in the ford The keen-edged pole-axe, or the shining sword, The red-hot metal hisses in the lake, Thus in his eye-ball hiss'd the plunging stake.
Page 468 - The other lines may be attributed to the antimony, strontia, &c. which enter into this composition. For instance, the orange ray may be the effect of the strontia, since Mr. Herschel found in the flame of muriate of strontia a ray of that colour. If this opinion should be correct, and applicable to the other definite rays, a glance at the prismatic spectrum of a flame may show it to contain substances which it would otherwise require a laborious chemical analysis to detect.
Page 484 - ... that it almost infinitely exceeds the limits to which chemical analysis of matter has heretofore reached. It predicts for us the most valuable conclusions on the distribution and arrangement of geological substances in their formation. Already the few investigations, which this memoir contains, lead to the unexpected conclusion that not only potassium and sodium but also lithium and strontium must be counted among the substances of the earth most widely scattered, though only in minute quantities....
Page 481 - ... animals and plants obtain from the ground. In another point of view, however, the presence of this chloride of sodium in the air is of interest. If, as is scarcely doubtful at the present time, the explanation of the spread of contagious disease is to be sought for in some peculiar contact-action, it is possible that the presence of so antiseptic a substance as chloride of sodium, even in almost infinitely small quantities, may not be without influence upon such occurrences in the atmosphere.
Page 498 - ... 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. 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 35 - The dexterity exhibited by the Hindoos in the Manufacture of wrought iron may be estimated from the fact of the existence in mosque of the kutub near Delhi, of a wrought iron pillar no less than 60 feet in length. This pillar stands about 30 feet out of the ground and has an ornamental cap bearing an inscription in Sanskrit belonging to the fourth century. It is not an easy operation at the present day to forge such a mass with our largest rolls" and steam hammers ; how this could be effected by...
Page 392 - Now, vessels of glass, of porcelain, and of all non-metallic substances, are destroyed by the means we employ for that purpose. Crucibles of gold and silver would melt at high temperatures. But platinum is cheaper than gold, harder and more durable than silver, infusible at all temperatures of our furnaces, and is left intact by acids and alkaline carbonates. Platinum unites all the valuable properties of gold and of porcelain, resisting the action of heat, and of almost all chemical agents. As no...
Page 473 - ... be now directed towards a bright surface, such as the flame of a candle, the spectrum of the flame is seen in the lower half of the field of the telescope on moving the latter through a certain angle round the axis of the foot.

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