The London, Edinburgh and Dublin Philosophical Magazine and Journal of Science

Forsideomslag
Taylor & Francis, 1840
 

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Side 55 - ... to extend my experiments and publish my view. At present I believe ordinary induction in all cases to be an action of contiguous particles, consisting in a species of polarity, instead of being an action of either particles or masses at sensible distances...
Side 277 - The strength of a pillar, with one end rounded and the other flat, is the arithmetical mean between that of a pillar of the same dimensions with both ends round, and one with both ends flat. Thus, of three cylindrical pillars, all of the same length and diameter, the first having both its ends rounded, the second with one end rounded and one flat, and the third with both ends flat, the strengths are as 1, 2, 3, nearly.
Side 336 - The corresponding oxygen stops also at the diaphragm, giving up its charge to the anion of the sulphate of copper. The copper and oxygen thus meeting at the intermediate point, partly enter into combination, and form the black oxide ; but from the rapidity of the action, there is not time for the whole to combine, and a portion of the copper remains in the metallic state, and a portion of the gaseous oxygen escapes. The precipitation of blue hydrated oxide doubtless arose from the mixing of a small...
Side 298 - I speak now not of periodical, but of secular changes. But the argument is complicated with the consideration of the possibly imperfect transparency of the celestial spaces, and with the cause of that imperfect transparency, which may be due to material non-luminous particles diffused irregularly in patches analogous to nebulae, but of greater extent — to cosmical clouds, in short — of whose existence we have, I think, some indication in the singular and apparently capricious phenomena of temporary...
Side 335 - We must conclude," from the above-mentioned principle, " that the only electrolyte which yielded was the sulphate of soda, the ions of which, however, were not the acid and alkali of the salt, but an anion composed of an equivalent of sulphur and four equivalents of oxygen and the metallic cathion sodium ; from the former, sulphuric acid was formed at the anode by...
Side 503 - ... the oblique impressions of the rain-drops register the point from which the wind was blowing at or about the time when the animals were...
Side 210 - ... stature and any attitude. By simply resting the back or side of the head against this ring, it may be kept .sufficiently still to allow the minutest marks on the face to be copied. The hands should never rest upon the chest, for the motion of respiration disturbs them so much, as to bring them out of a thick and clumsy appearance, destroying also the representation of the veins on the back, which, if they are held motionless, are copied with surprising beauty.
Side 44 - Agreeably to this or any other imaginable view of the subject, I cannot avoid considering it inevitable that each particle must have at least two poles. It seems to me that the idea of polarity requires that there shall be in any body possessing it, two opposite poles. Hence you correctly allege that agreeably to your views it is impossible to charge a portion of matter with one electric force without the other. (See par. 1177.) But if all this be true, how can there be a " positively excited particle...
Side 277 - The result for wrought iron is, that the strength varies inversely as the square of the length of the pillar, and directly as the power 3'75 of its diameter, the latter being nearly identical with the result obtained for cast iron ; while in timber, the strength varies nearly as the fourth power of the side of the square forming the section of the pillar. In like manner, the power of...
Side 277 - ... 3d. A long, uniform, cast-iron pillar, with its ends firmly fixed, whether by means of discs or otherwise, has the same power to resist breaking as a pillar of the same diameter, and half the length, with the ends rounded or turned so that the force would pass through the axis.

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