Epilepsy and other convulsive affections : their pathology and treatment / by Charles Bland Radcliffe.

  • Radcliffe, Charles Bland, 1822-1889.
Date:
1858
Catalogue details

Licence: Public Domain Mark

Credit: Epilepsy and other convulsive affections : their pathology and treatment / by Charles Bland Radcliffe. 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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    tlie pattern of the one which has been just described, or nearly so. The guage of the wire forming the coil in this instrument is number 38, or as nearly as possible that of the pattern coil, the weight of the wire entering into the coil 1 lb. 11 oz., the layers of the coil 154, the number of codings 20,020. The codings, therefore, are not quite so nume- rous as in the pattern coil—a difference owing in ad probability to the silk winding around the wire being somewhat thicker ; but the instrument to all appearance is not a whit less sensitive on this account. The needles were copied with as much exactness as possible, and the only difference in the astatic system is in the fact that the con- necting piece is made of aluminium instead of tortoise-shell. The whole system was a little lighter—4-5 grains, instead of 4-9 grains. The degree of astaticism was such as to make the needles arrange themselves at right angles to the magnetic meridian, or thereabouts. When in actual use, the galvanometer is placed upon a solid support where there will be as little vibration as possible, insulating pieces of glass are placed under the adjusting screws, and the coil is arranged so as to be across the magnetic meridian, or nearly due east and west. The electrodes may be on the same support as the coil or upon an adjoining table. In performing an experiment, the