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 . are made in two])ieces, to allow of windows.*Two paper collectors are gluedto each stationary plate. Theseterminate in points, which pro-ject into the windows madeby dividing the plates. The poles of the machine have metal combs on one end and a brass ball at theother. Extra combs have been added to draw off residual electricity,which accumulates in excess ; but these are grounded. Furthermoie, the machine has been encased, si
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 . are made in two])ieces, to allow of windows.*Two paper collectors are gluedto each stationary plate. Theseterminate in points, which pro-ject into the windows madeby dividing the plates. The poles of the machine have metal combs on one end and a brass ball at theother. Extra combs have been added to draw off residual electricity,which accumulates in excess ; but these are grounded. Furthermoie, the machine has been encased, simply to protect itfrom atmospheric changes. Cat-skin rubbers have been added. Thoyare of use only as a means of exciting the plates when, from any cause,induction shall have ceased. We call them the chargers of themachine. There have been many mechanical modifications ninde from time totime of the original model, which have not been here specified by me ;but as they do not in any way aflTect the principle of electrical induction,they are not of importance in this Fig. 172.—The Stationary Plate op the Origi-nal HOLTZ, SHOWING ITS AuMATURES AND Windows, with the Projections upon theArmatures. 654 LECTURES ON NERVOUS DISEASES. In the original Iloltz machine, a charge was primarily effected byrultbino- a piece of ebonite briskly witli cat-skin nntil it became highlycharged witii negative electricity, and then api)lying it closely to one ofthe paper collectors on the stationary plate of the machine. By the law of indnction the comb opposed to this paper collector becomeselectrically excited immediately. It at once deposits posiYtue electricififon the side of the revolving plate nearest to the comb, and takes nega-tive electricifif away from the revolving plate. Thns the revolving platebecomes podtively electrified to a very high degree at this point.
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Keywords: ., bookcentury1800, bookdecade1880, bookidlecturesonne, bookyear1888
