Page:Memoirs of the Geological Survey of Great Britain, Volume 1.djvu/458

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AND OTHER CONDITIONS OF MATTER.
445

ANP OTHBK CONDITIONS OF MATTER. 445

26. Chloride of bismuth was placed in tubes, which were inverted in the plate, filled with distilled water, over the poles of the magnet. A series of circles were immediately produced corresponding to the iron of the electro-magnet and its coils of copper wire. The quantity of sub- salt increasing, a series of very distinct diamagnetic curves formed, which exhibited a powerful repulsive force, as those from the north pole ap- proached those radiating from the south. These curves were, however, sometimes bent back, and at others doubled down, and exhibited a tendency to unite with curves proceeding from the other side of the same pole. Numerous experiments were made with the hope of tracing these dissimilar actions to some definable cause, but as yet this has not been determined. It may, in all possibility, be dependent upon the magnetic influence exerted on the fine particles in motion within the sphere of powerfol action, they being at the same time repelled by the force of the opposite pole. The consequences, under such circumstances, would probably be that the curves of radiation, forming near the axial line, would be driven across it, or turned back, according to the accident of the precipitated subchloride of bismuth being formed at the moment when the magnetic pulsation or oscillation is at a minimum ; or when it arrives at or is advancing towards its maximum ; or by crossing certain nodal points occurring between the successive and periodic impulses. We have, however, such curiously complicated actions to deal with, that we cannot, in the present state of the inquiry, without any knowledge of the laws which regulate the magnetic and diamagnetic forces, venture to do more than assume the possibility that our hypothesis indicates something like the cause of the efiects described.

27. Nitrate of bismuth shows the same order of arrangement, and the same peculiarities, as those just described (26).

28. A few experiments have been made with the oxides and salts of antimony, zinc, and lead. They all appear to give the same curves of radiations ; but as frirther experiments are intended upon these, and other metals of the same class, any notice of them is for the present deferred.

29. A warm saturated solution of the protosulphate of iron being poured in a copper dish, was placed, as in the other experiments, over the poles of the electro-magnet. As the solution cools, a gradual formation of crystals takes place, and if the proper strength of solution be hit, the necessity for which will be presently explained, the crystals arrange themselves in magnetic order, — that is, aloi^ the axial line, they form numerously, and in the experiment, the result of which is re* presented in Hg. 9, they arranged themselves in two well-defined lines extending, on either side, from one pole to the other* Crystals accu* mulated abundantly on the poles, and some indications of a ten*

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