Unpublished paper, 'On the direct production of heat by magnetism' by W R [William Robert] Grove Grove writes that soft iron, when magnetised, emits a sound or musical note. He also mentions an experiment of his own, published in January 1845, where a tube was filled with the liquid in which magnetic oxide had been prepared, and surrounded by a coil; this showed, to a spectator looking through it, a considerable increase of the transmitted light when the coil was electrised. Annotations in pencil on front page. Marked on front as 'To be printed'. Subject: Physics / Magnetism Received 24 May 1849. 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 the direct production of heat by magnetism'. 23 May 1849