prescribe a diet for the case in hand, or ignore it and avoid responsibility. The author agrees with Woods Hutchinson that there are dangers in undereating. By undereating he means the taking of food which is not only insufficient in quantity, but which is deficient in the elements whirh the body requires for its normal maintenance. Most of the systems of dietetics ignore the latter in some particular. The proper proportion of carbon, hydrogen, oxygen, sulphur, phosphorus, etc., in needed amount is a subject requiring scientific attention. Its application to the sick is not possible unless the physician knows its proper application to the healthy, normal individual. And after all, after this knowledge is gained the next and equally important task is the judging of the patient under treatment; not a class of men and women who are ill, but the one before you. He is not like any other being and he is a study in the application of dietetics.

VALUE OF LEMON JUICE. The Office Practitioner has an instructive article on the many excellent uses of the lowly lemon. The high-grade value of hot lemon juice in whiskey in incipient influenza-the grippe-and other violent fresh colds obtains in the action of citric acid on the invading disease before it develops to serious conditions beyond the bronchial and alimentary surfaces, thus not seldom aborting the trouble ere there are perilous complications to combat.

Diluted lemon juice in clysters will kill germs of Asiatic cholera in less time than any other applicable preparation known to the profession, and will serve a medical term in the inflammation or ulceration of typhoid fever equalled by no other appropriate remedy.

Mixed with an emulsion of castor oil, parts three; olive oil, part one; lemon juice, part one, and sodium chloride sufficient to taste, it is a valuable disinfect

ing purge, often curing diarrhea and dysentery promptly, and effective in yellow fever.

Strong black coffee, highly impregnated with lemon juice, is a slow but sure malarial cure, verified by me thousands of times in the absence of other medicines during tropical revolutions.

SMOTHERING THE BABY.

On the car one morning coming into town, relates Dr. Chas. E. Page, of Boston, I noticed a lady with a suspiciouslooking bundle in her lap, and I made bold to ask if there was anything alive under that shawl, and she said, “Yes, a little baby." "Well," I said, "you ought not to cover up a baby's face; they need the air. Thousands of babies die from want of right management," I said, “and one of the most serious things the little chaps are up against is lack of fresh air and free breathing."

As I stepped along, a slick-looking young man said to me: "Better let that lady alone and mind your own business." My reply was, "It is my business; what have you got to do with it?" "I am the baby's father." "Well," I said, "why don't you drown it? That is a better death than smothering." And I left him to his own reflections. It is quite a common practice, this covering baby's face.

VALUE OF FAMILY PHYSICIAN REFRACTING TO THE PATIENT.

L

EARTUS CONNOR points out that the hapless victims of eye troubles are everywhere, and unless their condition be promptly recognized and wisely managed, more or less irreparable damage ensues. Their loss of time, comfort and efficiency in the struggles of life can be minimized only as the watch-dog family physician is trained for their detection. The following observation is suggestive: Some time since, when traveling in the West, the writer was asked to examine the colonel of a United States regiment, because of his growing blindness. This was SO extreme that a 50-foot flag could not be seen at an elevation of 100 feet. For weeks his sight had been so bad that his wife was compelled to make out his reports. The army post was in charge of a medical officer accomplished in all else except simple refraction. In the post equipment was found only an old. Lebreich opthalmoscope, no atropin, no homatropin, or even cocaine. A solid extract of belladonna was found, the pupil dilated, and by the archaic ophthaimoscope an albuminuric neuroretinitis was observed. Inquiry revealed that he had been compelled to rise frequently at night to pass urine. This was found loaded with albumin and casts. In spite of the utmost haste to place him under rational management, the colonel suifered many severe convulsions ere it was accomplished. It is clear that had the post medical officer been trained in a working knowledge of simple refraction, he would have investigated the beginning failure of vision, detecting its cause, and given the distinguished officer a better chance for regaining sight and retaining vigor. Armed with a working knowl

edge of simple refraction, the family physician could detect cases allied to this and give them that prompt and rational treatment essential to best results.

CATECHISM OF REFRACTION. (Continued from page 611, October number.) Correction of Hyperopia.

Q. What is the chromatic test for hyperopia?

A.

The chromatic lens is a combination of cobalt lenses so arranged as to suppress all of the rays passing through the lenses except the violet and red. The violet rays are refracted to a greater degree by a given medium than are the red rays. Now, if the refraction of the eye be normal, the difference in the refraction of the two kinds of rays will not be sufficient to produce any sensible chromatic aberration, and the patient, viewing a candle flame through the lens, will see an ordinary white flame. But if the eye is hyperopic, the violet rays will not have to come to focus by the time they reach the retina, and the red rays will be still further from focusing, hence the appearance of the flame to a hyperopic eye is that of a red margin around a blue center.

Q. Describe the distance-type test. A. A hyperopic eye can, of course, read No. 6 type at 6 meters distance, just as well as a normal eye can. But a normal eye, reading this type at this distance, has its accommodation completely relaxed, so that a weak convex lens placed before the eye will blur the vision. The hyperopic eye, on the other hand, in reading No. 6 at 6 meters, is using some of its accommodation, so that if a weak convex lens is placed before the eye, it can, by relaxing its accommodation, still read the type with perfect clearness;

hence a weak convex lens does not blur vision in the hyperopic eye.

If we now keep trying stronger and stronger convex lenses we shall find one beyond which any further increase blurs vision; and this lens is the measure of the hyperopia of the eye. The best way, however, after once ascertaining that the eye is hyperopic, is to at once over-correct it with a powerful convex lens, and then proceed to reduce the correction by super-mounting stronger and stronger concave lenses, until we reach a point where vision is clear. The net convex correction then before the eye is the measure of its hyperopia. This plan is better than the other, because it induces gradual contraction instead of gradual relaxation of the ciliary muscle.

Q. What are the findings of the retinoscope in hyperopia?

A. As previously stated, if the eye were normal, the rays of light emerging from it would be parallel, and would therefore be brought to a focus on the retinoscope, a meter from the eye, by a 1 D. convex lens. If, however, the eye be hyperopic, the rays leaving it are divergent, and will need a stronger convex lens than 1 D. to bring them to a focus at 1 meter. The amount that the required lens is in excess of 1 D. is the measure of the hyperopia, and will be its proper correction.

The rule, then, is that if the shadow move against the mirror, and a convex lens of 1 D. does not give the point of reversal, the eye is hyperopic. We then try successively stronger and stronger convex lenses until we find one that gives this point. We then subtract from this lens the 1 D. which represents normality, and what is left is the measure of the hyperopia and its correction.

retina. In order to do so, he must assist their refraction with a convex lens. He therefore wheels successively stronger and stronger convex lenses in front of the sight hole of the ophthalmoscope, until he finds the one which gives him a clear view of the patient's fundus. That lens is the measure of the hyperopia, and its correction.

Q. What is the showing of indirect ophthalmoscopy?

A. The emerging rays being divergent, will strike the objective lens at a more and more obtuse angle, the further it is withdrawn, and so the image of the disc will diminish in size as we withdraw the objective lens. We then mount before the patient's eye stronger and stronger convex lenses until we find one with which the image remains stationary in size as the objective is withdrawn. This lens is the measure and correction of the hyperopia.

Q. Should the results of all these tests be identical?

A. Theoretically they should; but practically they rarely are. However, if each test is carefully conducted and verified, the discrepancy, if any, ought not to be much. In hyperopic cases it is then advisable to prescribe the highest result that is obtained.

Q. Is all of the hyperopia measured by these tests?

A. Not as a rule. The hyperopia, if it has existed for any length of time, as it usually has, has registered itself in some permanent spasm or hypertrophy of the ciliary muscle which persists during the examination, and prevents the total amount of error being uncovered. That which is uncovered by the tests is called manifest; that which remains undetected is called latent hyperopia. The

A. Since the rays emerging from the hyperopic eye are divergent, it is manifest that the relaxed eye of the observer can not bring them to focus upon his own

"unlocked" all at once by paralyzing the eye with atropin, or gradually, by correcting first all the manifest error, and having the patient come back every month or two to further correct the

latent error as it uncovers itself. The latter plan is preferable in general practice, if circumstances are convenient. (To be continued.)

AMBLYOPIA AND ITS CORRECTION.

Geo. A. Rogers, in the Optical Journal-Review, says that a hyperopic amblyope will accept plus spheres without impairing distant vision, or distant vision may be improved to a considerable extent with them. The amblyopia is not corrected by the lenses, and perhaps vision may not be. But the plus spheres, if they do not impair distant vision, should be prescribed just the same. They relieve the accommodation to the same extent in an amblyope as in another

case.

A myopic amblyope has two causes operating together to impair distant vision. The correction of the myopia may bring distant vision up from 20/200 to 20/60, but be incapable of going farther. There is more correct focalization of the images, which is one of the causes of impaired distant vision, although the amblyopia prevents further improvement. The amblyopia is not going to be helped by the lenses, but neither is it going to be injured, and 20/60 is considerable improvement of vision to be obtained in such cases. A much less improvement is sufficient reason for prescribing the correction.

In astigmatism the correct cylinder improves the amblyope's vision very sensibly, though perhaps not as pronouncedly as it would an eye with normal acuity. By the latter term we refer to the eye's capacity to see when corrected. Real acuity of vision is the degree of sensitiveness of the sensory field and has nothing to do with impairments of vision due to imperfect focalization. We can not judge a person to be amblyopic because his vision is below normal; nor can it be said that his acuity is below normal because he is unable to see 20/20.

Acuity of vision is what the eye is capable of seeing, not what it sees. It is not a question of the correctness of the camera or of the lens in the camera, but of the sensitivity of the sensitized plate upon which the images are imposed. You can't make a good photograph, no matter how perfect the camera, without a good plate. You can't make a good photograph with a perfect plate and a poor

camera.

When plate and camera are both imperfect, and there is a way to perfect the camera, there is no reason why it should not be done. It will improve matters somewhat, perhaps a good deal, although perfection is not to be expected. You can not know what the amblyopic element amounts to until you have corrected the refraction.

Amblyopes derive nearly as much benefit from correcting lenses as other people, sometimes more. A corrected image may improve retinal sensitiveness, and the amblyopia be gradually dissipated. The correction, the true correction, can never do any harm.

LENS AND PINHOLE.

Focus two sharply defined objects, for example, two church spires seen against the sky, at such a distance that their images shall be separated on the ground. glass by a moderate interval, of, say, 1 inch. Mark the positions of the images. by attaching bits of stamp paper to the screen. Then remove the lens and substitute for it a pinhole made in the center of a disc of thin tin plate. Adjust your screen until the faint images of the chosen objects projected by the pinhole occupy exactly the positions marked for those images which were formed by the lens. The distance from screen to pinhole will now be equal to the equivalent focal length of the lens under test. In other words, this is the distance from the ground glass at which we should have to mount a single lens, such as a spectacle lens, which was the optical equivalent of the corrected objective.

EXOPHORIA. Lander, in the Cleveland Medical Journal, defines exophoria as a tendency of the eyes to deviate outward so that unless held in place by continuous effort, which is controlled by the power of fusion, they diverge from the point of fixation.

Exposition By the use of a Maddox rod, which consists of a glass rod or series of rods mounted in a disc to fit the trial frame, the natural image of a small flame, such as a candle or gas flame, placed at 20 feet distance in a dark room is converted into a streak of light. Assuming that the Maddox rod is placed horizontally before the right eye, the patient will see a vertical streak of light with that eye and the flame with the left eye.

Fach eye now having a separate object of widely different shape to look at, the power of fusion is destroyed and, as a result, each eye will occupy its independent position in the orbit. If there is perfect equilibrium between the lateral recti muscles of the eyes the streak of light will pass through the flame; if there is a tendency to convergence the streak of light will be to the right of the flame, while, if there is a tendency to divergence, the streak of light will be to the left of the flame, which condition will indicate exophoria. This can be measured by prisms which enable the patient to fuse the images.

WHAT ARE "STRONG EYES?'

The Optical Journal-Review propounds this question. It is far from uncommon for lay persons to speak of their parents or of themselves having "strong eyes." If urged to explain what they mean by this term, the explanation is that newspapers may be read without glasses, or small objects may be seen at a great distance, and their identity recognized. But to the refractionist strong eyes would be those in which the visual acuity, with the error of refraction corrected, if any, is above normal. By this

test a great many eyes which are claimed to be "strong" would be found to be just the contrary, for the person who can read without glasses is one who is myopic, or rarely in the case of elderly people, one whose accommodative powers have persisted to an unusually late age. In both of these cases it does not follow that the scientific test of the refractionist would show any extraordinary ocular strength. As to those who can see things far away and recognize them, this is more the result of experience than acute vision. It has been found that the people of the plains who can recognize objects at great distances, will not show any higher acuity of vision, when suitably tested, than others who can not perform such feats. Sailors who are very expert at recognizing the nature of objects in the water so far away that the traveler can not see anything distinctive in them, are at a loss on the plains where the objects they try to see at a distance are unfamiliar to them.

PARALLELISM IN BINOCULARS.

The Optician calls attention to a defect often noticed in cheap binoculars which occasions discomfort independent of any error of focus. This defect is a want of parallelism between the axes of the little telescopes which form the binocular. It is easily detected when the instrument is held to the eyes by passing one hand through the lines of sightacross the objectives, so as to occlude each of them in turn. If the movement is made quickly, it will be observed that objects seen through one and the other telescope, alternately, seem to move or jump at the instant of the change. And the amount and direction of this change of apparent position measures the error of adjustment of the framework of the binocular glass. The defect, which is unconsciously neutralized by the eye muscles in binocular vision, is much less serious when it occurs in the horizontal than in the vertical direction.