On the transient magnetic state of which various substances are susceptible / [Sir W. Snow Harris].

  • Harris, W. Snow (William Snow), Sir, 1791-1867
Date:
1831
Catalogue details

Licence: Public Domain Mark

Credit: On the transient magnetic state of which various substances are susceptible / [Sir W. Snow Harris]. Source: Wellcome Collection.

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    tween two glass circular checks, so as to obtain a ring of nearly the same dimensions as the others, subsequently separating the influence due to the glass alone. 29. The place which the following metals appear to occupy in the scale of magnetic energy, and their comparative influence, as resulting from this investigation, is given in the succeeding Tables. Table IX. Metals. Rolled Silver. Rolled Copper. Cast Copper. Rolled Gold. Cast Zinc. Cast Tin. Cast Lead. Solid* Mercury. Cast Antimony. Fluid Mercury. Cast Bismuth. Compara-n tive magne- > tic energy .J 39 29 20 16 10 6.9 3.7 2.0 1.3 1.0 0.45 Table X. Alloys. Cast Copper and Zinc in equal parts. Cast Copper and Bis- muth in equal parts. Cast Zinc and Bismuth in equal parts. Comparative } energy .. $ 12 2.3 1.4 30. Although considerable pains have been taken to make the foregoing Table as perfect as possible, yet it cannot be considered as anything more than a useful approximation; there are many conditions peculiar to this inquiry to be yet investigated, which seem for the present to preclude the possibility of obtaining results quite conclusive. The metals employed were in as great a state of purity as they could be obtained in the ordinary way of commerce ; some of them, more especially the copper, gold, and silver, may be considered as very nearly without alloy. 31. If the preceding investigations are of any importance, they seem to be in great measure conclusive, as to the cause of the influence of a rapidly * The comparative influence of solid mercury must be taken as a rough approximation; the bar in this ring in air, as nearly as could be ascertained, performed about 150 vibrations between 45° and 10°; whilst, in an analogous ring of rolled copper it performed about fourteen vibrations; in free space in air, it performed 232.