Unpublished paper, regarding a magnetic experiment on board the iron steam vessel Bloodhound by Captain [Edward John] Johnson

Description

Johnson undertakes experiments with the view of ascertaining whether the action of steam upon the hull of an iron vessel affects a compass, properly placed, in any degree that may be of practical importance in its navigation; and also whether the keeling of the vessel produces any alteration in the deviations, or disturbs a compass so placed to any considerable extent. The former question is, from the results of these experiments, resolved in the negative; but with respect to the second, it appears that the deviations produced by keeling are very marked, and could not be safely disregarded. These observations prove the necessity that exists for ascertaining the deviations of the compass in all ships, not only at the beginning and end of their voyage, but likewise at intermediate stations; as also constant observation of the course which the ship may be steering.

Marked on back as 'Archives 4 May 1848 S H C [Samuel Hunter Christie]'.

Subject: Magnetism / Marine engineering

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 'Magnetical experiments on board H. M. iron steam vessel "Bloodhound"'.

Reference number

AP/30/7

Earliest possible date

08 June 1847

Physical description

Ink on paper

Page extent

8 pages

Format

Manuscript