On electro-magnetic clocks / Professor Brande.

  • Brande, William Thomas, 1788-1866.
Date:
[1852]
Catalogue details

Licence: Public Domain Mark

Credit: On electro-magnetic clocks / Professor Brande. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Stereoscopes (on Brewster’s principle) illustrating the Phoenomena of Binocular Vision, as explained by Professor Wheatstone. [Exhi- bited by Mr. Claudet.] Talbotvpes from the Great Exhibition, by Mr. Henneman. A Telescopic Camera Lucida and a Microscope with improved Mechanism, by Mr. C. Varley. Specimens illustrating Claussen’s Processes of Preparing Flax, Hemp, &c. [Exhibited by Dr. Ryan.] Minerals. [Exhibited by Mr. Highley, jun.] Model (in similar materials) of the Lion, Bull, and Column from Nineveh in British Museum. [Exhibited with permission of Dr. Layard.] Carving on wood by Mr. W. G. Rogers. W. R. Hamilton, Esq., F.R.S. &c. Vice-President, in the Chair. Mr. Brands began by adverting to the various opinions which had been entertained in reference to the mutual relations of elec- tricity and magnetism, previous to the grand discovery of Oersted in 1819. As soon as the influence of an electrical current upon a magnetic needle had been developed by the researches of that eminent philosopher, many most important applications of the fact almost of necessity suggested themselves, amongst which the wonders of the electric telegraph were to be included. Another result of Oersted’s discovery was the electro-magnet; the power namely, of conferring by proper adjustments of an electric current any degree of magnetism upon a bar of soft iron: and inasmuch as these magnetic energies cease the moment that the electric current ceases, so we have it in our power to render any conve- nient form of soft iron, such as bars, or horse-shoes, powerful magnets at one moment, and at the next, entirely withdrawing all their powers ; and this, simply by making and breaking the contacts upon which the flow of electricity from voltaic arrange- ment depends. In this way a horse-shoe magnet was made alternately to lift and drop a weight, to raise and depress a loaded lever, and to bend and release a spring. These effects were merely due to the attractive force of the electro-magnet upon holders and WEEKLY EVENING MEETING, Friday, January 30. Professor Brande, On Electro-Magnetic Clocks.