Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

is large ; the nectitant membrane becomes prominent and ad- vances upon the eyeball. If the animal then continues to live a certain time after the operation, the eye becomes smaller and in effect shrunken, and drawn back in its orbit. These experi- ments were repeated and confirmed by Dr. Pupuy, Dr. Breschet, and Dr. John Reid. But more recently it is discovered, that if the pupil has become constricted after the section of the cervi- cal sympathetic nerve, it can again be dilated if the cephalic end of the nerve be electrized. In the year 1852, Professor Claude Bernard published his most interesting and valuable researches on the physiological offices of the great sympathetic nerve. He goes on to say, that after the section of the nerve, or after the destruction of the superior cervical ganglion, besides the phenomena long before noticed by M. Pourfour-du-Petit, the following are produced: a less or greater constriction of the nostril, and of the mouth, on the same side; an increase in the circulation of the blood, with an augmentation of heat and sensibility in the head. He observes, also, that if the cephalic (upper) end of the cut ganglionic nerve be electrized, then all these phenomena ob- served after, and in consequence of the section of the nerve, will equally disappear, and can even be exaggerated in the extreme. Not only does the constriction of the iris, that is produced by cutting the sympathetic nerve, disappear from being electrized, but the pupil becomes even larger than normal; the eye is plumper and more prominent; the temperature, which had been exalted, is diminished to a healthy standard ; the nostril and ear of the animal, which had been red and injected, become quite pale again ; but as soon as the electric influence is removed, then all the phenomena that first attended the section of the nerve, gradu- ally reappear. But they can be made to disappear, again and again, by the repeated applications of the electric current to the nerve above the cut. Besides, if we apply a drop of ammonia to the conjunctiva of a dog, in which the section of this gan- glionic nerve has been made, the pain will oblige the animal to keep the eyelids strongly closed ; and then, if the cephalic end of the cut nerve be electrized, he will immediately open his