GENTLEMEN,—Among the minor ills of life few occupy a more important place than those which arise from eye-strain. Many a headache, many an attack of giddiness, many an z , instance of "brain-fag," and many a so-called "nervous breakdown " tells only too surely of an unsuspected error of refraction, or of subnormal accommodation, or of a muscular imperfection of the eyes, all of which may be relieved by suitable spectacles. These cases come in the first instance under the notice of the family

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... ical adviser rather than of the ophthalmic surgeon. It is therefore a matter of no little consequence for him to be acquainted with the peculiarities of eye-strain, so that patients may be freed from their discomfort in the speediest possible way. What I have to say will not deal with those physical peculiarities of the eye which give rise to the several conditions known as hyperopia, myopia, or astigmia. They have been made the subject of a former Middlemore lecture by Mr. Henry Eales.l I On the contrary, my remarks will deal with the several conditions known and believed to result from eye-strain, and in describing them I shall touch upon the evidence on which our knowledge is based. GENERAL REMARKS. 1. Hom to recognise symptomatic eye-strain. -Whenever a headache, migraine, vertigo, or "tic" is induced or made worse by use of the eyes and relieved by rest we may safely assume it is due to eye-strain. That supposition is strengthened (paradoxical though it may seem) if the patient possesses sight which when estimated by the test-types is found to be normal or super-normal. It is a suspicious circumstance if headache is complained of after a visit to a theatre or a picture gallery, or a journey by train, tram, or car. There is more than the proverbial grain of truth in the epigram of an American physician who remarked that there was nothing particularly characteristic about the headache of eye-strain, except that the subject rarely suspected that his eyes were at fault. This point has been emphasised anew by Dr. James Hinshelwood, of Glasgow.2 z Then there is the fact that an ocular reflex can often be inhibited for the time being by putting a drop of atropine (or other cycloplegic) into the patient's eyes. Lastly, it can scarcely be repeated too often that no eye can be pronounced to be normal unless its refraction has been estimated by a competent surgeon under the influence of a cycloplegic. 2. The kind of patient.-Slight errors of refraction are most likely to cause distress in persons who have inherited or acquired an unstable nervous system, the" neuropathic " disposition, as Dr. George T. Stevens called it.3 In my opinion, this factor dominates the entire question of eye-strain, especially in its severer manifestations. Women and children suffer more readily than men, among whom the highly strung are the more liable. The higher classes are more prone than the lower; the cultured than the uncultured. Clerks, teachers, stenographers, dressmakers, typewriters, students, and others compelled by occupation to use the eyes for hours at a time are particularly subject to the symptoms of eyestrain. The general health of the patient is by no means devoid of influence. It is clear that an error of refraction or oc muscular balance is more likely to cause distress if the patient is in poor health, as from influenza, or debilitated, as from lactation or recent confinement. It is not uncommon for the trouble to disclose itself for the first time under such 1