difficulties incident to the performance of the visual act.

As has already been said, every oculist recognizes the fact that asthenopia is a complaint resulting generally from ocular defects or insufficiencies of the ocular muscles. Yet it is equally well known that this more immediate and much less severe form of irritation does not always yield to the means employed for its treatment. But if we compare the results of treatment of asthenopia with the results obtained in the treatment of headaches by similar means, we can not fail to see that the latter form of complaint yields as often to treatment directed to correction of anomalies of refraction and accommodation or of muscular insufficiencies as does the former. Hence we may logically draw the conclusion that headaches are as generally the result of disturbing ocular conditions as is asthenopia.

It is to be further observed that the relief is not the result of temporary stimulation of nervous energy, such as might result from the use of electricity, or of certain drugs, or a change of air or surroundings. Either or all of these measures might bring relief in certain cases, but if the fundamental cause remains, it is only relief, and can not be properly regarded as a cure, of the predisposing tendency.

In cases of temporary nervous disturbance, resulting in headaches, the agencies above mentioned may be used with advantage, but they certainly have no power to remove an hereditary cause.

Further consideration of the treatment of this

special class of troubles may be reserved for consideration under the general discussion of therapeutical measures in nervous complaints.

Nearly related to this class of troubles is migraine, a complaint often classed with neuralgia, but which has characteristics so clearly defined that it may well rank as a distinct form of nervous disturbance.

MIGRAINE, OR SICK-HEADACHE.

Paroxysms occur with greater or less regularity in respect to time, the intervals being in some cases only a few days, in others a month or more. The attack commences in most cases with a feeling of lassitude and dull headache, the eyes are painful, and the act of turning them quickly or far is attended with distress. The effect of light is disagreeable, and there is mental disquietude. In some instances the attack is ushered in by great disturbance of vision, sometimes described as glimmerings and confusion. At other times the visual defect assumes the form of hemiopia, or even of complete blindness. The visual disturbance lasts from a few seconds to an hour, and such attacks are known as "blind headaches."

The subject of an attack, after a few hours of these premonitory symptoms, resorts to the bed, the pain over and through the eyes becoming more and more intense, and the effect of light more tormenting. Slight sounds or feeble currents of air are often unendurable, and nausea and vomiting supervene. The pain is in many cases confined to one side, and in some uniformly to the same side, in various attacks. In others the

pain is alternately located on one or the other side, and, in case of visual disturbance of one eye only, the headache is often situated upon the opposite side of the head to the eye affected. The headache as well as the visual disturbance may, however, be bilateral.

In a few cases of "blind" headaches, in which the fundus of the eyes have been examined with the ophthalmoscope during the period of visual disturbance, the retina has been found pale and brilliant, the optic disc unusually white, and the main arteries somewhat irregularly contracted in their course. In these cases the field of vision has been found to be contracted in a striking manner, in some instances one half of the field being completely lost, while in others the central field was gone, imperfect sight only remaining at the periphery.

A night's sleep may bring relief, or the paroxysm may continue for several days, during which delirium or loss of consciousness may become prominent symptoms.

The attack being over, there may remain some symptoms of the nervous prostration for a day or two, but the patient is soon more than usually well for a period of one or several days, and the subjects of the complaint are often extremely vivacious and energetic in the intervals between the attacks. This is, however, not always the case, as a certain proportion of the subjects of this malady are rarely free from a dull headache, pains at the spinous process of the lower cervical vertebra, and at the lower angles of the

scapula. Palpitation of the heart and general nervous irritability are also among the continuous symptoms.

The history of the affection often goes back to the earliest recollections of the patient, and in nearly all cases a vast number of supposed remedies have been tried, sometimes with slight temporary relief, but more frequently without any good results. In a considerable number of cases the affection is developed during school-days, a circumstance which has led to the abhorrent supposition that it results mostly from impure thoughts and practices.

Fortunately, this is a gross libel upon a class of humanity on the whole characterized by frankness and intelligence. If we remember that, at the age of from eight to fifteen, nearly all of the children in whom this affection is found are at school, closely pursued by examinations and a multitude of studies, we shall see that the demand upon the ocular muscles is excessive, and that this demand is for the most part made in crowded school-rooms, where the air is vitiated, and nerves and muscles are thereby rendered less capable of enduring the strain. Again, these subjects of migraine are, as a class, unusually ambitious, and such children maintain advanced positions in their classes at an expense of eye-strain even greater than that which attends the exercise of the eyes of the less ambitious pupil. If, added to this, there is an anatomical or physiological reason for unusual strain in doing the ordinary work of the eyes, we have a combination of circumstances conspiring against the strength of these children.

This is not only the more true but the more generous explanation of the occurrence of these attacks, at this period of life, than the one alluded to; and the author, after a careful investigation of both sides of this question, feels justified in earnestly protesting against the unjust insinuation.

Some patients suffer less when absent from home, occupied in travel or repose, or when engaged upon light duties which permit them to be much in the open air. Tonic medicines also sometimes increase the intervals between the attacks and render them less severe. The temporary relief, however, which lengthens the intervals or modifies the attacks can not be regarded as a cure. And a cure can only be assumed when so long a period of time has elapsed since a last attack that, under ordinary circumstances, in the particular case, a very large number of attacks could reasonably have been expected. Again, as in case of most functional nervous diseases, there is a tendency to a change in the form of the complaint, and one subject for several years to migraine may find that he has no longer sick-headaches, but is a sufferer from some form of neuralgia, perhaps equally distressing with the former complaint. Such a case can not be regarded as cured. There has been simply a change in the manifestation of nervous irritation. In all these cases there is an underlying cause, which is to be found and removed. This accomplished, a permanent cure may be anticipated.

Here, as in the case of the more ordinary forms of headache, it will be found that ocular defects play a