patient's own sensations, and never allowed to remain in longer than three or four days. If there be much discharge present, the wool or cotton may require removal daily. It is astonishing with what adroitness a patient will sometimes hit off the necessary position of the cotton, even after the practitioner has failed to adjust it. Notwithstanding some ingenious attempts at explanation, we still require a feasible solution as to how this remedy acts.

Mr. Toynbee has recently recommended a thin plate of vulcanized India rubber or gutta percha, attached to a wire stem, as an artificial tympanic membrane, in lieu of the wool or cotton remedy. I have no experience of it; but I doubt its general applicability.

In the foregoing chapter I may to some have appeared prolix; but, upon a subject comparatively so new in English literature, so little studied, and consequently so little understood by practitioners in general, it was not possible to explain my meaning without entering into minute descriptions. Moreover, from the circumstance of the membrana tympani being the part most easily examined, being that most frequently affected, and, consequently, affording the safest means for diagnosis either for deafness arising from affections peculiar to itself, and confined to its own structure, or which it exhibits in common with other and deeper-seated structures similarly diseased, it frequently affords us not only the surest but the only faithful indication for forming an accurate diagnosis. If aural diseases were as attentively studied in these kingdoms as ophthalmic or obstetric affections, then would the lengthened description of cases be unnecessary; but where do we find, throughout the whole circle of our periodical literature, half-adozen well observed and accurately noted cases of disease of the ear in a twelvemonth? Faithful observation and clinical records of disease are now more required in this than in any other branch of medical science.

See Medical Times and Gazette for February 12, 1853.

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CHAPTER VI.

DISEASES OF THE MIDDLE EAR AND EUSTACHIAN TUBE.

Anatomy of the Cavitas Tympani.-Apertures, Ossicula, and Investing Membrane.-The Eustachian Tube and Tonsils.-Congenital Malformations of the Middle Ear.— Wounds and Injuries; Hemorrhage and Serous Effusion.-Inflammations: Acute Otitis; Otorrhoea; Subacute Otitis; Exanthematous and Typhoid; Acquired Dumbness; Facial Paralysis.-Rheumatic Otitis; Periosteal; Caries.-Diseases of Mastoid Cells.-Affections of the Ossicula.-Morbid Growths in the Tympanum: Polypus; Exostosis. Catarrhal and Chronic Otitis: Ablution, Fumigation, and Bougie Exploration of Tympanum.-Malignant Fungus.-Diseases of the Eustachian Tube; Foreign Bodies in; Inflammation; Obstruction.-Throat Deafness.-Enlarged Tonsils and Cleft Palate.

A

LTHOUGH I have separated the diseases of the Eustachian tube from those of the cavitas tympani in the Nosological Table, in accordance with the anatomical basis observed in their general division; still, in a pathological point of view, these two parts may as fairly be classed together as the diseases of the middle ear and the mastoid cells.

The middle division of the auditory apparatus, the tympanum or cavitas tympani, is that space between the membrana tympani externally, which separates it from the auditory tube, and the outer wall of the internal ear or labyrinth. It resembles the form of its external septum, but is rather more irregular in its circumferential boundary. It is somewhat wedge-shaped, being narrow below and broad above, owing to the oblique position of the membrana tympani, and measures about three-eighths, or from that to half an inch in its longest diameter. In the dry bone it has five special outlets,-externally into the osseous meatus;-internally by two small apertures, which communicate with the labyrinth, called from their shape the round and the oval window,-two proceeding from the circumference; of these, that anteriorly, and a little below the middle horizontal line, is the entrance of the Eustachian tube, which communicates with the throat; and one or more openings lead in the adult into the mastoid cells superiorly and

posteriorly. Viewed from without, by making a section of the temporal bone immediately beyond the groove for the attachment of the membrana tympani, we observe upon its inner wall a projection of densely hard bone dividing the two apertures already alluded to, both of which are placed in the posterior half, and consequently immediately opposite the external outlet of the osseous auditory canal and the posterior vibrating portion of the membrana tympani. This protuberance is the promontory caused by the projection of the cochlea: the inferior opening is the fenestra rotunda, somewhat triangular in shape, and in the recent state closed by a delicate membrane analogous to the membrana tympani, and which may be called the internal drum-head, which separates the tympanum from the extremity of the cochlea, and hence called the fenestra cochleæ. As this membrane serves to transmit vibrations of sound, and is the only barrier to the escape of the fluid contained within the labyrinth, it is manifest that any interference with its functions, any alterations or organic changes in its structure, or its total destruction from sloughing, ulceration, or caries of its bony attachment, must be attended with considerable impairment, if not total loss, of hearing. When the tympanic cavity is exposed by extensive destruction of its outer membrane, we do not see the little membrane of the cochlear fenestra; the whole looks one uniform red surface, and in this state the physiology of hearing has not yet been satisfactorily explained; but I presume that the waves of sound impinge directly upon this membrane, and sensations are thus conveyed to the internal ear. That the membrane vibrates is proved by experiment, and one use of it may be to allow the fluid contained within the vestibule, when pressed upon by the base of the stapes-covering, like a lid, the fenestra ovalis-to bulge a little into the cavity of the tympanum. But that this latter must be a secondary object is proved by the amount of hearing possessed by persons who have suffered from extensive destruction of the membrana tympani, or have even lost some of the ossicles.

The superior opening is, as its name implies, oval or ovoid for the reception of the base of the stapes, which fits into it somewhat like a stopper, or the piston of a cylinder, and is attached to its circumferance by a ligamento-fibrous membrane, which allows a double motion to the small bone which it surrounds,-a

stopper-like one by which it is forced towards the cavity of the vestibule, with which this opening communicates,—and a lateral or oscillating one by which each of its extremities can be made to press inwards in turn.* The surface of the promontory is grooved for the ramification of the tympanic branches from the glosso-pharyngeal nerve. Traversing the superior wall of the tympanum, immediately above the fenestra ovalis, is the aqueduct of Fallopius for the transmission of the facial portion of the seventh pair of nerves, which projects somewhat into the roof of the tympanic cavity, and the relations of which have already been remarked upon at page 214. Posteriorly and immediately below this conduit of the facial, we observe a little conical eminence called the pyramid, in the apex of which there is a depression leading into an opening which gives insertion to the stapedius muscle.

From the large sinus in the roof of the tympanum, or sometimes by one or two openings in addition, the mastoid cells communicate freely with the cavitas tympani, and it is of great importance to bear this communication in mind, when inflammation attacks the tympanum, which space, as well as these mastoid cells, are separated from the cavity of the cranium by a thin and often delicate lamina of bone, pierced by several small apertures for the transmission of vessels to the dura mater, which adheres intimately to the superior surface of the bone at this place.

Anteriorly and somewhat inferiorly the whole side of the tympanal cavity, from the attachment of the membrana tympani in front to the root of the promontory behind, may be seen the smooth trumpet-shaped entrance of the Eustachian tube; and not, as is described in books, commencing by a small aperture; on the contrary, it is the widest part of the bony portion of that canal. Along its posterior margin, somewhat above the middle, a delicate concave shelf of bone stands out, which forms the floor of a canal,

See the splendid work of Professor Hyrtl of Vienna, upon the Comparative Anatomy of the Ear, "Vergleichend-anatomische Untersuchungen über das innere Gehörorgan des Menschen und der Saugethiere." See also, in addition to the various works upon Anatomy, and Mr. Wharton Jones' Essay in the Cyclopædia of Anatomy and Physiology, the recently published paper by Mr. Toynbee "On the Functions of the Muscles of the Tympanum in the Human Ear," in the British and Foreign Medico-Chirurgical Review for January, 1853.

completed by fibrous membrane, through which the tensor tympani muscle plays. The length of the bony portion of the Eustachian tube is about half an inch, and of an irregular elliptical figure, sometimes resembling a mere slit, and seldom admitting, even in the dry bone, anything larger than an ordinary-sized dressing probe, and certainly not capable of giving transit to the great majority of the bougies and other instruments recommended by aurists to be passed through it for the purpose of clearing it, or of exploring (?) the cavitas tympani.

The parts contained within the tympanum are:-the ossicula auditus, the muscles by which these bones are moved, and the chorda tympani nerve, which in its circuitous course traverses the upper part of this cavity.

This chain of small bones has three points of attachment,-the membrana tympani, and the fenestra ovalis, between which they stretch, and the walls of the tympanum, which afford them support. They consist of the malleus or hammer, the incus or anvil, and the stapes or stirrup; to which some anatomists have added a fourth bone, under the name of the orbicular, but which is now believed to be a portion of the incus. All these bones, when placed together, form an arched chain of levers, extending across the upper and back portion of the tympanal cavity, and which by their motions serve to convey vibrations of sound from the membrana tympani, to which they are attached externally, to the fenestra ovalis, where the inner leg of the arch is fastened; and also to place both the membrana tympani and the membrane of the fenestra rotunda in particular states of tension or relaxation, whereby they can be affected by sounds more or less grave or acute. For this latter purpose their mechanism is under the control of muscles probably of the voluntary class. The malleus or hammer consists of a body fitted into a corresponding surface in the incus; a head rising into the tympanic sinus above the attachment of the membrana tympani; a manubrium or handle stretching down between the lamina of the latter structure, to which it gives insertion and support, as already explained at page 215; a tubercle between the body or neck and handle, which is always recognisable through the membrana tympani;