. The medical and surgical uses of electricity. . ermanent composition, through which a movable rod is raised or 288 ELECTRO-THERAPEUTICS. lowered by the operator. Tube No. i is given a high resistance to con-trol high-tension currents of great power. Tube No. 2 has a much lowerresistance for currents of less penetrative energy. The rheostat may beoperated in the secondary circuit of any high-grade induction apparatusto which suitable connections are attached. No claim is made that the rheostat is a faradic meter, but it is cali-brated in ohms of resistance that admit of accurate registration
. The medical and surgical uses of electricity. . ermanent composition, through which a movable rod is raised or 288 ELECTRO-THERAPEUTICS. lowered by the operator. Tube No. i is given a high resistance to con-trol high-tension currents of great power. Tube No. 2 has a much lowerresistance for currents of less penetrative energy. The rheostat may beoperated in the secondary circuit of any high-grade induction apparatusto which suitable connections are attached. No claim is made that the rheostat is a faradic meter, but it is cali-brated in ohms of resistance that admit of accurate registration of the doseadministered at any given time. There is an existing need for a standard method of recording the treat-ment administered, and thus imparting a uniform and intelligible value tothe reports of clinical cases, now so lacking in precision and method suggested by Monell is a practical one. To record the cur-rent strength of any application, he takes the value represented by theresistance cut out of his calibrated Fig. 73.—Sinusoidal Apparatus (Mcintosh). Milliammeters.—What the compass is to the mariner the milliam-meter is to the electro-therapeutist. Without it he would often findhimself quite at sea, and would be liable either to get no results or, incases especially of internal treatment, when the resistance is low, accom-plish far more harm than good. The meter Fig. 77 is a good one, hav-ing been calibrated with great care and from standard electric test scale indicated by the lower figures gives the low reading of mil-liamperes, by fraction of milliampere. The upper scale gives the highermilliampere readings. The instrument is sensitive and the pointer willoscillate quite freely, but it is supplied with a dead-beat attachment, sothat the pointer can be immediately brought to rest by pressing the knob. APPARATUS FOR ELECTRO-THERAPEUTICS. 289 It is of a type similar to the Weston & Kennelly meters, and is practicallyunaffected
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1896
