the horizontal meridian of the patient. The same analysis will show that the points of a horizontal line in the background will form a sharp horizontal line in the focal plane of the vertical meridian, but a broad horizontal stripe in the focal plane of the horizontal meridian. Therefore, an ophthalmoscopist accommodated for the horizontal meridian of his patient will see the vertical lines of the fundus distinctly, the horizontal lines indistinctly, and vice versa, Q. E. D.

The mode of examination is the following: Always with relaxed accommodation you look into an eye and turn the revolving disk with the auxiliary glasses until one set of fine vessels is perfectly plain. If, at the same time, the others are likewise plain, the eye examined is not astigmatic. If, however, they are not so plain, you turn the disk until they are. The greatest difference of refraction gives you the principal meridians, and, at the same time, the degree of astigmatism and its kind, simple, compound, or mixed.

Now, gentlemen, you will tell me: "This is all very well, and we have known that before; but with what degree of accuracy can astigmatism be determined in that way?" To this I answer: "It can be done with the same, or at least almost the same, accuracy as the ophthalmoscopic determination of simple ametropia, where a difference in refraction of 0.5 D, i. e., 2, is easily noticed." Let me illustrate this by one example, referring to the wife of one of the medical gentlemen here present. Mrs. Dr. R., æt. 30, asthenopia and amblyopia all her life.

20

RIGHT EYE. S. No improvement with spherical glasses.

O. S. vertical vessels clearest with 0.5 D (71⁄2); i. e., horizontal meridian H 0.5 (1⁄2). Horizontal vessels clearest with 3.5 D (†) ; i. e., vertical meridian H 3.5 ().

Astigmatism. hyperop. composit. 4.0 D (). against the rule, is the more strongly curved.

The horizontal meridian,

Functional examination. Glasses from + je to c; axis 15° give S 38. Prefers c 15°.

LEFT EYE. Sf.
20 Not improved with spherical glasses.

) ; i. e., vertical meridian H 3.5 (1%). The horizontal meridian here also,

O. S. vertical vessels clearest with 0.0 D (1); i. e., horizontal meridian E. Horizontal vessels clearest with + 3.5 D ( Astigmat. hyperop. simplex 3.5 (). against the rule, the more strongly curved.

Functional examination. Sees best with from c to c; axis 0° (horizontal), S38. Prefers c 0°.

With both glasses together sees very comfortably and reads without inconve nience.

This is a high degree of astigmatism, and S was greatly im

proved by the glasses. In other cases I found with the O. S. equally high or still higher degrees, but S was less improved, and the patients preferred weaker glasses. This discrepancy is no reason to distrust the ophthalmoscopic determination; on the contrary, the functional examination did not bring out the full amount of astigmatism, which, at least in part, was what is called incorrigible. Though, as I have said, for practical purposes the determination with cylindrical glasses should principally be relied upon, i. e., govern the formula for the spectacles the patient has to wear, at least for some time, in such cases I would use still other subjective tests-radiating lines, stenopæic apparatus-in order to see how far they agree with the ophthal moscopic determination. It is not without interest, nor without importance, to ascertain the degree of meridional asymmetry in cases of so-called incorrigible astigmatism, as the cause of the amblyopia might erroneously be sought in the optic nerve or brain.

The ophthalmoscope I prefer for this and all purposes is one with twenty-eight glasses in a single disk, covered and centred, the mirror fixed (not tilting), the hole 3.5 mm. in diameter. The workmanship (by Miller Bros.) is unsurpassed, there being no reflexes, no jarring in the easily moving disk, and the image perfect. I also use an O. S. with thirty-three glasses, but find twenty-eight sufficient. The ophthalmoscopes with two whole or fractionary disks are all inconvenient, and the advantage of a tilting mirror is, to a large degree, more imaginary than real.

A CASE OF PERICHONDRITIS AURICULE.

DEMONSTRATED BY H. KNAPP, M.D.,

NEW YORK.

THE demonstration was accompanied with the following remarks:

The genuine inflammation of the perichondrium of the ear has not received due attention on the part of authors. I therefore beg to present a typical case of it.

Patient, a lad of about 15, always healthy in body and mind, had, four months ago, a circumscribed swelling in the right auditory canal behind the tragus. It was thought to be a furuncle, and incised. Some viscid liquid escaped. The swelling diminished, but went over to the posterior part of the canal, and from there successively to the concha, and all over the auricle, with the exception of the lobule. Distinct fluctuating prominences were opened, and viscid liquid escaped. By probing, the perichondrium was found detached from the rough cartilage. A drainage tube and pressure bandage were applied. The posterior surface was red and evenly swollen, but there never was any fluctuation. About two months after the beginning, the swelling was at its height. The auricle presented a swollen, misshapen mass, as you see in the photograph. Then gradually the fistulous openings closed, the swelling diminished, and the auricle, as you see it now, also from the second photograph, is much reduced in size and irregularly shrunken. The lobule has been unchanged.

CONTRIBUTIONS TO OTOLOGY.

BY S. D. RISLEY, M.D.,

PENNSYLVANIA.

MR. PRESIDENT AND GENTLEMEN: The following cases, selected hurriedly from my case-book of ear disease, have seemed of sufficient importance and value, not only to place permanently upon record in the annals of this society, but to justly demand a few moments of the valuable time during this annual meeting.

They are selected, the first as an illustration of the value of perfect rest and freedom from exposure in the treatment of serious and threatening ear disease; the second and third cases as marked illustrations of how simple local conditions may give rise to violent storms in the entire nervous system, and by the severity and malignant portent of the symptoms awaken the gravest apprehensions, and lead the physician or surgeon to an unnecessarily grave prognosis.

CASE I.-Acute Purulent Inflammation of Ear, involving Mastoid Cells, and causing Meningeal Irritation, treated by rest in bed.

P. T., a boy aged 13, with bright red hair, freckled face, and fat, flabby tissues, consulted me at the Eye and Ear Dispensary of the Episcopal Hospital at Philadelphia, on a cold, damp day, in April, 1879, barefooted, and thinly clad, complaining of a profuse discharge from the right ear, with marked tinnitus and severe right hemicrania.

He staggered into the clinic room like a person just up from a protracted fever. He was pale, weak, and trembling. His hands were cold and clammy, and profuse beads of perspiration stood out on his forehead. The pulse was rapid, quick, and thready, easily compressible. There was great mental hebetude, so that but little information could be gleaned from him. But the following history was gained from his mother, who came with him. He was taken from his bed to be brought to the hos