Unpublished paper, 'On a peculiar source of deterioration of the magnetic powers of steel bars' by William Sturgeon

Description

Sturgeon undertakes various experiments on the changes in the magnetic force of steel magnets produced by subjecting them to blows with a wooden mallet, or other modes of creating tremors or vibrations among their particles. He concludes that the mechanical agitation is sufficient to considerably, permanently reduce magnetic power. In every case, after reaching a certain point, magnetic power attains its maximum, a fact which implies, in every magnet, the possession of a specific retentive force, of which it can not be deprived by any further mechanical commotion of its particles. The more highly a bar is magnetised, the more it becomes susceptible of a loss of power by agitation.

Annotations in pencil throughout.

Subject: Physics / Magnetism

Received 27 May 1845. Communicated by Samuel Hunter Christie.

Written by Sturgeon in Kirby Lonsdale [Cumbria, England].

Whilst the Royal Society declined to publish this paper in full, an abstract of the paper was published in volume 5 of Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society] as 'On a peculiar source of deterioration of the magnetic powers of steel bars'.

Reference number

AP/27/25

Earliest possible date

23 May 1845

Physical description

Ink and graphite pencil on paper

Page extent

16 pages

Format

Manuscript