26 Dublin Quart. Jour., 1867, p. 431.

27 Wiener med. Presse, No. 29, p. 715.

28 Dublin Quart. Jour., xlvi. 187.

The condition of the eyes and of vision in this disease is directly due to pressure of the exudation at the base of the brain upon the nerves and blood-vessels that supply these organs. One of the most striking peculiarities of the countenance of a patient at the beginning of an attack is the diffused and uniform redness of the conjunctivæ. In children it has a light tint, but a darker one in adults, and in some cases the eye becomes suffused with an extravasation of blood. The conditions of the pupil are also very peculiar. Very long ago it was observed to undergo sudden changes from contraction to dilatation, or the reverse. Dilatation is, however, its ordinary condition, especially in the fully-formed attack. Very often the pupils of the two eyes are in opposite states. In cases of long duration, with great exhaustion, they are almost invariably dilated. Photophobia is not uncommon, and oscillation of the pupils and spasmodic movements of the eyeball have frequently been observed. Strabismus is a symptom of very ordinary occurrence, particularly when other paralytic or spasmodic phenomena exist. It may be convergent or divergent, but most commonly is the former, and may be either a transient or a permanent symptom. Like other individual symptoms, it may be present rarely or frequently in a particular epidemic.

Blindness has been repeatedly observed. At first it seemed to be noticed as a transient symptom only. Fish (1809) states that it was sometimes the first deviation from health, and then was followed by paralytic spinal symptoms. He also observed that sight was sometimes restored in a few hours, and in no case did he know it to be permanently lost. American as well as European physicians, however, have met with many cases in which the sight was seriously and permanently impaired or altogether destroyed. In 1873 the changes affecting the eye were more fully and accurately described, especially those which tend to the structural injury of the organ. The abnormal appearances included cloudiness of the media, discoloration of the iris, irregularity of the pupils, and their obstruction with exudate. In exceptional cases the cornea ulcerated, and the globe collapsed after losing its contents. Ordinarily, however, says Lewis, "no ulceration occurs, and as the patient convalesces the oedema of the lids, the hyperæmia of the conjunctiva, the cloudiness of the cornea and of the humors gradually abate, and the exudation in the pupils is absorbed. The iris bulges forward, and the deep tissues of the eye, viewed through the vitreous humor, which had a dusky color from hyperæmia, now present a dull white color. The lens itself, at first transparent, after a while becomes cataractous, and sight is lost totally and for ever."

Impairment or loss of hearing has been occasionally observed during the successive epidemics of this disease, even from the beginning of its history, and it was early noticed that the symptom was often quite independent of any cognizable lesion of the ear itself. It was also observed that the sense of smell sometimes became impaired or was lost at the same time with that of hearing. More recently, Collins reported a case in which the patient lost the sight of one eye and became permanently deaf in both ears. Knapp states that in all of thirty-one cases examined by him the deafness was bilateral, and, with two exceptions of faint perception of sound, complete. Among twenty-nine cases of total deafness only one seemed to give some evidence of hearing afterward.29 This surgeon holds that the deafness results from a purulent inflammation of the labyrinth, and his judgment has been confirmed by Keller and Lucas. When the impairment of hearing occurs simultaneously, or nearly so, in both ears, it is probable that the chief cause of the deafness is the pressure of the plastic exudation in which the auditory nerve is imbedded. Such deafness is rarely permanent. When the loss of hearing, whether complete or partial, does not improve, there is reason to believe that the internal ear has suffered great and incurable changes of structure. Sometimes this follows a distinct attack of suppurative inflammation of the middle ear; but as complete and permanent deafness sometimes occurs without being preceded by any such affection, it must be inferred that atrophic changes have taken place in some portion of the nervous apparatus of hearing. It is stated by Moos that of sixty-four cases of recovery from cerebro-spinal meningitis, which showed disturbance of hearing as a sequel, one-half manifested in addition a more less disordered equilibrium. Of these twenty-nine were totally deaf on both sides, two totally deaf on one and hard of hearing on the other side, and one case had merely impaired hearing in both ears. The disturbance of locomotion had existed for periods varying from three weeks to five years from the inception of the disease, and was chiefly characterized by a staggering or waddling gait.30 In the deaf-mute institutions at Bamberg and Nürnberg it is said that out of 91 pupils, 80 owed their infirmity to this disease (Ziemssen). Salamo states that some awake out of sleep totally deaf, and remain so for a long time, or, it may be, permanently (Moos).

29 Smith, loc. cit.

30 Mening. Cerebro-spinal epid., p. 11.

The expression of countenance in this disease is peculiar. When the pain in the head is severe and paroxysmal the features are apt to be violently distorted; when it is more persistent the face assumes a fixed or rigid expression, or is at the same time dull, particularly after a long continuance of the pain. In the apoplectic form the expression may be set and stupid, but the features have neither the dark, dull, swollen, and duskily-flushed aspect of typhus, nor the languid, sleepy expression, and circumscribed flush on the cheek which are so characteristic of typhoid fever. Except during absolute insensibility in rapidly fatal cases there is a look of greater intelligence than belongs to either of the diseases mentioned. Indeed, in the beginning of the attack in regular cases the distinctive facies presents pale and sunken features, with paleness of the skin over the whole body.

Delirium in this disease exhibits a great many degrees and varieties. It may occur among the earliest symptoms in certain rapid cases not of the congestive type, but is more apt to arise on the second or third day in those more typically developed. It may be mild, reasoning, hysterical, or maniacal, or it may change from one to another of these forms during the same attack. Fish states that it is apt to be violent if it comes on at the commencement of the illness, but that when it begins at a later period it is milder, and sometimes playful, the patient being sociable and humorous. All good observers have furnished similar descriptions of this symptom; some have added that the mental condition is often desponding and apprehensive, and others that certain patients remain sombre and silent; and it sometimes happens that the delirium comes on abruptly, as when a patient "woke suddenly in the middle of the night and began to hum tunes, to fancy that people were conversing with him," etc. (Gordon).