Page:Memoirs of the Geological Survey of Great Britain, Volume 1.djvu/465

452 452 INFLTJSNCB OF VOLTAIC ELBCTBICITT

1846, and then allowed slowly to dry between the galyanic plates, the results were so curious as to merit a particular description (Ilg. 12).

46. On the zinc side, to the depth of an inch and a half, there were distinct lines parallel to the plate, not extending from the top to the bottom of the mass, which was 12 inches deep ; but after proceeding about six inches down, exhibiting a tendency to bend inwards. Upon breaking the clay open when dry, it was found that after proceeding towards the centre of tiie mass they again turned outwards, and formed indeed curved lines from one point of the zmc plate near the middle to its lowest point The consolidation on tiie copper side was very dis- tincdy marked, and the appearance was that of a continuation of hard nodular masses along tiie lines of tiie voltaic current This consolida- tion had evidendy been produced by the drawing of particles from the centre of the mass, in which a large hollow (a) was formed ; and this was found to be a portion of a very decidedly marked line of action from the bottom of the zinc plate to the centre of the copper plate (b and from that pomt again to the top of the zinc plate (c). As these curved lines approached the zincous side, they were crossed and split by laminations, although very distinctly continued. We have tiius evidence afforded us of two distinct forces in action, or perhaps it would be safer to say, indications of two lines of power along which the particles arrange themselves. It was found, upon close examination, that the curved lines above described were formed by the metallic copper, and the car- bonate of copper and zinc — (sulphate of copper was used on the side of the copper plate, and muriate of soda on tiie zinc side). Upon breaking the clay transversely, the appearance of the mass was in the highest degree interesting and instructive. From near the top on the zinc side, a marked dark space was seen to describe a line inclining from the ho- rizon at about the angle of 40. When it approached the copper side, it was gradually bent back, and formed a curve to the bottom of the zinc plate. This curve was formed in parts near the copper plate of laminae of metallic copper, whilst more distant from it specs of carbo- nate of copper appeared which were particularly confined to the marked space, and indeed represented an artificial mineral lode.

47. A di£Bculty at present presents itself which will no doubt dis- appear when we have had the experience of frirther investigation. This is to account for the arrangement of the particles of clay in parallel planes, according to the order of the diamagnetic cur?es, and of the dis- position of the metallic salts, and metals themseWes, even of those which are not magnetic, zinc and copper, along what appears to be the true circuit of the electric current

It was observed very soon after the experiment just described was first established, that the fluid on one side was elevated considerably

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