The motive power of the human system : with the symptoms and treatment of chronic diseases / by H.H. Sherwood.

  • Sherwood, H. H. (Henry Hall)
Date:
1841
Catalogue details

Licence: Public Domain Mark

Credit: The motive power of the human system : with the symptoms and treatment of chronic diseases / by H.H. Sherwood. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    to the number and arrangement of two poles only—of a positive and a negative pole. We must therefore see whether the magnetic forces would of them- selves, without artificial aid, produce five poles in this order of arrange- ment, and for this purpose we may use a circular plate of steel which would correspond with a middle horizontal section of the brain. A cir- cular saw plate, eight inches in diameter, and the tenth of an inch thick, with a hole in the centre of one inch in diameter, was accordingly sub- jected to actual experiment in the following manner: The middle of the plate or disc was carefully let down in a perpen- dicular direction on the middle of the positive pole of the galvanic bat- tery, and after having remained there a moment, was raised from its posi- tion in a perpendicular direction, turned over, and the opposite side of the plate placed upon and then removed from the negative pole of the battery in the same manner. The plate was then covered with white paper, and fine iron filings were strewed over it, when they were immediately arranged by the forces in the plate in the manner seen in fig. 8. FIG. 8. a