The term "nerves" still persists, in the old sense, in both botany and entomology, which speak of the "nerves" of a butterfly's wing, or the "nervation" of a leaf, meaning simply the branching, fibrous framework of each. It comes in the nature of a surprise to most of us to learn that "nerves" are real things. I shall never forget the shock of my own first convincing demonstration of this fact. It was in one of the first surgical clinics that I attended as a medical student. A woman patient was brought in, with a history of suffering the tortures of the damned for a year past, from an uncontrollable sciatica. It was a recognized procedure in those days (and is resorted to still), when all medical, electrical, and other remedial measures had failed to relieve a furious neuralgia, for the surgeon to cut down upon the nerve-trunk, free it from its surrounding attachments, and, slipping his tenaculum or finger under it, stretch the nerve with a considerable degree of force. Whether it acts by merely setting up some trophic change in the nerve-tissue, or by tearing loose inflammatory adhesions which are binding down the nerve-trunk, the procedure gives excellent results, nearly always temporary relief, and sometimes a permanent cure. The patient was placed upon the table and anaesthetized, and the surgeon made a free, sweeping incision down the back of the thigh, exposing the sciatic nerve. He thrust his finger into the wound, loosened up the adhesions about the nerve, hooked two fingers underneath it, and, to my wide-eyed astonishment, heaved upward upon it, until he brought into view through the gaping wound a flattened, bluish-gray cord about twice the size of a clothesline, with which he proceeded to lift the hips of the patient clear of the table. In my ignorant horror, I expected every moment to see the thing snap and the patient go down with a bump, paralyzed for life; but I never doubted after that that nerves were real things. Though it has nothing to do with this discussion, for the benefit of those of my readers who cannot bear to have a story left unfinished, I will add that the operation was as successful as it was dramatic, and the patient left the hospital completely relieved of her sciatica. When at last it was clearly recognized that the nerves were concerned in the sending of messages from the centre to the brain, known as _sensory_, or centripetal, and carrying back messages from the brain to the muscles and surface, known as _motor_, or centrifugal,--in other words that they were the organs of the mind,--still another source of confusion sprang up, and that was the determination on the part of some to regard them from a purely mental and, so to speak, spiritual point of view, and on the part of others to regard them from a physical and anatomical point of view. This confusion is of course in full riot at the present time.