Practical hydropathy, including plans of baths and remarks on diet, clothing and habits of . surface, however, being lined by a prolongation ofthe skin of the auricle. Membrane of Tympanum.—The internal extremity ofthis tube is inserted into an orjening leading into the middle ear, which is inclinedto the axis of the tube at an angle of about 45^. Over this opening, which isslightly oval, an elastic membrane, called the membrane of the tympanum, istightly stretched, like parchment on the head of a drain. Inlig. 435 theseveral parts of the ear are shown divested of the surrounding bony m
Practical hydropathy, including plans of baths and remarks on diet, clothing and habits of . surface, however, being lined by a prolongation ofthe skin of the auricle. Membrane of Tympanum.—The internal extremity ofthis tube is inserted into an orjening leading into the middle ear, which is inclinedto the axis of the tube at an angle of about 45^. Over this opening, which isslightly oval, an elastic membrane, called the membrane of the tympanum, istightly stretched, like parchment on the head of a drain. Inlig. 435 theseveral parts of the ear are shown divested of the surrounding bony matter;and to render their arrangement more distinct, they are exhibited upon an en-larged scale. The concha, with the tube leading mwards from it, marked a,terminates at the inner end, as already stated, in the tense membrane of thetympanum placed obliquely to the axis of the tube. The resemblance of this tubeand the concha to the speaking or hearing trumpet is evident, and the physicalpurposes which it fulfils arc obviously the same, being those of collecting and 42G HANDBOOK OF Fig. 435. conducting the sonorous undulations to the membrane of the tympanum, whichwill vibrate sympathetically with them. The Middle Ear is a cavity surrounded by walls of bone, which, however, arcremoved in Tig. 435, to render visible its internal structure. An openingcorresponding to the membrane of the tympanum is made in the external wall,and the external part of the inner ear shown in the figure is part of its innerwall. The inner and _ outer walls of this cavity are very close together; but thecavity measures, vertically as well as horizontally, about half-an-inch, so that itmay be regarded as resembling the sounding-board of a musical instrument,composed of two flat surfaces, placed close and nearly parallel to each other, thesuperficial extent of which is considerable compared with their distance cavity is kept constantly filled with air, which enters it through a
Size: 1608px × 1555px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookd, booksubjectbaths, booksubjecthydrotherapy
