that a quantity of food which has been injudiciously taken, lying as it does undigested in the stomach, may of itself greatly aggravate the neuralgia, by irritation transmitted to the medulla oblongata. In such a case vomiting may directly relieve the nerve-pain. When the patient awakes from sleep, the active pain is gone. But it is a common occurrence—indeed it always happens when the neuralgia has lasted a long time—that a tender condition of the superficial parts remains for some hours, perhaps for a day or two. This tenderness is usually somewhat diffused, and not limited with accuracy to the foci of greatest pain during the attacks.

Sick headache is not uncommonly ushered in by sighings, yawning, and shuddering—symptoms which remind us of the prodromata of certain graver neuroses, to which, as we shall hereafter see, it is probably related by hereditary descent. In its severer forms, migraine is a terrible infliction; the pain gradually spreads to every twig of the ophthalmic division; the eye of the affected side is deeply bloodshot, and streams with tears; the eyelid droops, or jerks convulsively; the sight is clouded, or even fails almost altogether for the time, and the darts of agony which shoot up to the vertex seem as if the head were being split down with an axe. The patient cannot bear the least glimmer of light, nor the least motion, but lies quite helpless, intensely chilly and depressed, the pulse at first slow, small and wiry, afterward more rapid and larger, but very compressible. The feet are generally actually, as well as subjectively, cold. Very often, toward the end of the attack, there is a large excretion of pale, limpid urine.

Another variety of trigeminal neuralgia which infests the period of bodily development is that known as clavus hystericus: clavus, from the fact that the pain is at once severe, and limited to one or two small definite points, as if a nail or nails were being driven into the skull. These points correspond either to the supra-orbital or the parietal, or, as often happens, to both at once. But for the greater limitation of the area of pain in clavus, that affection would have little to distinguish it from migraine, for the former is also accompanied with nausea and vomiting when the pain continues long enough; and in both instances it is obvious that there is a reflex irritation propagated from the painful nerve. The adjective hystericus is an improper and inadequate definition of the circumstances under which clavus arises. The truth is, that the subjects of it are chiefly females who are passing through the trying period of bodily development; but there is no evidence to show that uterine disorders give any special bias toward this complaint. Both migraine and clavus are often met with in persons who have long passed their youth; but their first attacks have nearly always occurred during the period of development.