Human physiology : designed for colleges and the higher classes in schools and for general reading . THE EAR. 277 Eustachian tube. Winding passages of the internal ear. the handle of the hammer is fastened to FIG- 15°- the middle of the drum, the base of thestirrup is fastened to another drum, cover-ing the hole or window, opening into thevestibule of the winding passages. Thereare three very delicate muscles which movethese bones. One of them relaxes thedrum of the ear, and another makes it DRUM QF THE EARmore tense; and thus the drum is put into .,„ .. . 1 wilh Uie bones. the right states of
Human physiology : designed for colleges and the higher classes in schools and for general reading . THE EAR. 277 Eustachian tube. Winding passages of the internal ear. the handle of the hammer is fastened to FIG- 15°- the middle of the drum, the base of thestirrup is fastened to another drum, cover-ing the hole or window, opening into thevestibule of the winding passages. Thereare three very delicate muscles which movethese bones. One of them relaxes thedrum of the ear, and another makes it DRUM QF THE EARmore tense; and thus the drum is put into .,„ .. . 1 wilh Uie bones. the right states of tension, to accommodateit to the various kinds of vibration that come to it. This is amatter of some importance, for it is plain that while a relaxeddrum can vibrate properly to grave sounds that enter the ear,it must be tense, in order to respond properly to the vibrationsof the air in the higher notes. 416. The cavity of the tympanum (h Fig. 148) in which thelittle bones are, and which is beyond the drum, communicateswith the mouth by the Eustachian tube g. If you shut yourmouth, and c
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Keywords: ., bookauthorhookerwo, bookcentury1800, bookdecade1850, bookyear1854
