United States or Uruguay ? Vote for the TOP Country of the Week !
Anatomists speak of an outer or external ear, a middle ear, drum, or tympanum, and an inner ear, or labyrinth. The external, middle, and internal ear are separated by dotted lines. Into it opens 5, Eustachian tube, leading from back of throat; 4, membrana tympani or drum-head, closing the middle ear off from the external ear.
These lie side by side and are named, from their relations to other parts, the scala vestibula, the scala tympani, and the scala media. *The Scala Vestibula and the Scala Tympani* appear in cross section as the larger of the canals. The former, so named from its connection with the vestibule, occupies the upper position in all parts of the coil.
This internal canal is 'Is actually in the house, sir; and, when you are so shortly to be as I expect 'Closed at the further end by the membrana tympani 'Joined together in holy matrimony 'Under which is carried a branch of the fifth pair of nerves 'I say, sir, when you are so shortly to be married to your cousin Marionetta 'The cavitas tympani Is he going to be married?
Similar cases were reported in the recent naval engagements between the Chinese and Japanese. Wilson reports two cases of rupture of the membrane tympani caused by diving. Roosa divides the causes into traumatic, hemorrhagic, and inflammatory, and primary lesions of the labyrinth, exemplifying each by numerous instances.
It diminishes or abolishes muscular contractility respectively when applied through the circulation or directly. It coagulates myosin and albumen. It causes insalivation by paralysis of the secretory fibers of the chorda tympani; increases the flow of bile; has no action upon the spleen.
Both the scala vestibula and the scala tympani belong to the outer portion of the internal ear and are, for this reason, filled with the perilymph. At their upper ends they communicate with each other by a small opening, making by this means one continuous canal through the cochlea. This canal passes from the vestibule to the tympanum and, in so doing, goes entirely around
The area of the membrana tympani is about twenty times as great as the membrane of the internal ear which is acted upon by the stapes. The force from the larger surface is, therefore, concentrated by the bridge of bones upon the smaller surface.
In the second place, the middle ear provides a means for concentrating the force of the sound waves as they pass from the membrana tympani to the internal ear. This concentration is effected in the following manner: 1.
The outer layer is continuous with the lining of the auditory canal; the inner is a part of the lining of the middle ear; and the middle is a fine layer of connective tissue. Being thin and delicately poised, the membrana tympani is easily made to vibrate by the sound waves that enter the auditory canal. In this way it serves as a receiver of sound waves from the air. It also protects
If the tumour is seated close to the membrana tympani, and has a broad and sessile base, then it cannot be excised or noosed with any degree of success. It must therefore be treated by the daily application of the solid nitrate of silver, applied exactly to its surface; and, in the intervals of application, the use of any collyria may be had recourse to.
Word Of The Day