Lectures on nervous diseases from the standpoint of cerebral and spinal localization, and the later methods employed in the diagnosis and treatment of these affections . grow finer and finer tillthe maximum point is reached. Such a dial ivill not be graduated aroundits entire circumference^ as the maximum point will be reached before the * Every galvanometer Bbould measure at least quarters of the first milliampere to beconsidered worthy of indorsement. 628 LECTURES ON NERVOUS DISEASES. DC^ of the circle on cither side nre re(iiiired. One of my own galvanom-eters is graded into equal degrees o
Lectures on nervous diseases from the standpoint of cerebral and spinal localization, and the later methods employed in the diagnosis and treatment of these affections . grow finer and finer tillthe maximum point is reached. Such a dial ivill not be graduated aroundits entire circumference^ as the maximum point will be reached before the * Every galvanometer Bbould measure at least quarters of the first milliampere to beconsidered worthy of indorsement. 628 LECTURES ON NERVOUS DISEASES. DC^ of the circle on cither side nre re(iiiired. One of my own galvanom-eters is graded into equal degrees on one lialf of tlie dial, and on theother half it is calibrated to milliamperes. Within the past few years the cllorts of Erb, Eulenbnrg, and Bern-hard in Germany, Gaiffe in France, and De Watteville in England haveawakened the profession to the necessity of accurately measuring thecurrent-strength employed upon a patient by means of a reliable galva-nometer. To their views I lend my most hearty support. As well can 1conceive of a boiler without a steam-gauge, or of a drug-store without ascale, as a galvanic battery without a galvanometer, provided its possessor. Fig. 150—A Galvanometer Dial. (After De Watteville.) The lower halfof the circle is grad-uated to milliamperes; the upper half to degrees of equal distance. One serious criticism canbe made of this dial, viz., that it does not indicate fractions of the first milliampere of cur-rent. Io my mind, a galvanometer-needle deflection for the first milliampere of currentshould be sufficient to show at least a quarter or an eighth of a milliampere. This fault iscommon to all vertical milliampere-meters with which I am acquainted. Even Hirschmannsinstrument does not entirely overcome it, 1 am at work at present upon a new form of mil-liampere-meter, which I hope will remedy this serious objection and at the same time allowthe needle deflections to be read easily when the eye is on the same level as the needle. aims at scientif
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Keywords: ., bookcentury1800, bookdecade1880, bookidlecturesonne, bookyear1888
