Proceedings of the Royal Society of London, Volume 21

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Page 172 - The Geology of Pennsylvania. A Government Survey, with a General View of the Geology of the United States, essays on the Coal Formation and its Fossils, and a description of the Coal Fields of North America and Great Britain. Illustrated with plates and engravings in the text. 3 vols. 4to, cloth, with portfolio of maps i5 oo ROSE (JOSHUA, ME) The Pattern-makers
Page 243 - Report of the Astronomer to the Marine Committee, Mersey Docks and Harbour Board, for the year 1S71.
Page 275 - The heat required to act upon a compound, so as to render its spectrum visible, dissociates the compound according to its volatility : the number of true metallic lines which thus appear is a measure of the dissociation ; and doubtless as the metal lines increase in number the compound bands thin out.
Page 82 - Since it appeared that the purest and densest vapour alone gave the greatest number of lines, it became of interest to examine the spectra of compounds consisting of a metal combined with a nonmetallic element. Experiments with chlorides are recorded. It was found in all cases that the difference between the spectrum of the chloride and the spectrum of the metal was that under the same spark-conditions all the short lines were obliterated. Changing the spark-conditions, the final result was that...
Page 482 - ... observed that each time that the secondary circuit is closed the needle swings to the right, at once resuming its former position in the same manner as after mechanical irritation. No difference in the effect is observable when the direction of the induced current is reversed. The observation may be repeated any number of times, but no effect is produced unless an interval of from ten to twenty seconds has elapsed since the preceding irritation. h. If the part of the concave surface of the leaf...
Page ix - AR Results of the comparisons of the standards of length of England, Austria, Spain, United States, Cape of Good Hope, and of a second Russian Standard, made at the Ordnance Survey Office, Southampton.
Page 482 - The same series of phenomena present themselves if the sensitive hairs of a still expanded leaf are touched with a camelhair pencil. d. If the closed leaf is gently pinched with a pair of forceps with cork points, the effect is the same. e . If the leaf-stalk is placed on the electrodes, as before, with the leaf attached to it, the deflection of the needle due to the stalk-current is increased whenever the leaf is irritated in any of the ways above described.
Page 156 - The hotter the discharging body, whether isolated or earthconnected, the more nearly alike do + or — electricities behave in being discharged ; but at certain temperatures distinct differences are noticed. The — electricity, in all cases of difference, is discharged with greater facility than the + . Attempts are made to measure the critical temperatures at which earth-connected hot iron...
Page 485 - Foreign Secretary, Prof. Alexander William Williamson, Ph.D. ; other members of the Council, Francis Maitland Balfour, MA, I.
Page 483 - Let us conceive, then, of an Algebra in which the symbols x, y, z, &c. admit indifferently of the values 0 and 1, and of these values alone. The laws, the axioms, and the processes, of such an Algebra will be identical in their whole extent with the laws, the axioms, and the processes of an Algebra of Logic.

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