Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.
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anastomoses with the nerves of the face, and also animates the radior fibres of the iris, and these act as the dilators of it. If, then, the cervical sympathetic nerve he excited, at the upper por- tion of the spine, by electric currents, the radial fibres of the iris very decidedly contract, as any extensor muscle, and thus overbalance, at least for the time, the circular fibres of the iris; for these latter, it is well known, act as the constrictors of it; and hence dilatation of the pupil must result. It is further found, that by the section of this particular nerve, the pupil of the eye becomes greatly and permanently constricted. The cir- cular fibres of the iris, not being ramified by this nerve, are left to act in their normal state ; while the section has caused in the radior fibres a complete paralysis, and consequently a prepon- derating, permanent constriction of the pupil of the eye. Effects of Electric Currents on the Organs of Sense. For operating on these, we may choose an instrument out of any of the three classes of machines that we employ for producing electricity, as all forms of it act upon the organs of sense, but differently, though all arc admissible. From my own experi- ence, and that after due consideration, I am disposed to decide that the primary galvanic currents have the most marked and beneficial effects on these delicate organs when they are deranged and diseased. I am not alone in this important observation, and if most effective and remedial here, why not elsewhere in the organism ? To use the galvanic current for arousing- action and toning-up, as in cases of nervous deafness, and nervous blindness, whether complete or partial,—of debilitated eye mus- cles, or deficient secretion, or even where excessive and morbid secretion of the lachrymal and salivary glands, — then I should say one electrode must be situated low on the cervical portion of the spine, while the other is directed to the part affected. In these cases we should always be careful to begin very gently, as witli only one element of a Daniell's battery, or with but the the very least electro-magnetic current, and then feel the way up the scale to a point of bearable endurance ; but never in any