A new point in the diagnosis of Graves' disease / by R. Norris Wolfenden.

  • Wolfenden, Richard Norris.
Date:
[1887]
Catalogue details

Licence: Public Domain Mark

Credit: A new point in the diagnosis of Graves' disease / by R. Norris Wolfenden. 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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    the method of examination, and the same spots of the patient's body should always be taken, viz., one electrode on the nape of the neck and the other on the top of the sternum, for the same reason. It is ridiculous to talk of using any number of cells of a battery (though it is often done), for batteries vary in strength from day to day, and it should always be a rule, whatever the current is to be used for, to estimate with the resistance coil and galvanometer the exact strength of the current about to be applied. Ten, twenty, or forty cells means nothing; but o 10, 20 milliamperes means a scientific dose. The former is like throwing a jugful of medicine at a patient, the latter like giving him a properly weighed dose. The method of taking the strength of the current is indicated in the following diagram: ^ Fig. 1.—E, resistance coil. G, galvanometer. B, constant cun-ent battery. ^ I append here the note of a practical electrician, Mr. J. B. Thisleton, of Old Quebec Street, London, with wbom the questions raised in this paper have been the subject of frequent consultation : '' Each Leclanche or sulphate of mercury cell in good working order and freshly charged should give a deflection of at least 1 5 milliamph'es, with a total resist- ance in the circuit of 1000 ohms. The object of using the 1000 ohm coil is to eliminate any errors from a slightly increased internal resistance in any of the cells, which, owing to the large resistance of the human skin, would not affect the passage of the current through it; 1000 ohms is also a very convenient resistance, because with this and a galvanometer divided in milliamperes we are able to see at a glance the electromotive force of any cell, and with any ordinary cell the greater its electromotive force the greater the cun-ent that will pass through the body or any other similar resistance to its passage. The electromotive force'of a cell is in no way dependent upon its size, and by including a large resistance,[such