Human physiology : designed for colleges and the higher classes in schools and for general reading . THE EAR. 283 Beautiful arrangement of the nervous fibrils in the cochlea. where the nerve terminates, as at 10 in Fig. 153, much morehighly magnified. You see the loop-like termination of thtjnervous fibrils. You can readily see that every vibration ofthe fluid would make an impression upon these nervous fibrilsthus distributed upon this delicate membrane, which has thefluid upon both sides of it. 424. The distribution of the nerve is after a different man-ner in the cochlea. Here there is no l
Human physiology : designed for colleges and the higher classes in schools and for general reading . THE EAR. 283 Beautiful arrangement of the nervous fibrils in the cochlea. where the nerve terminates, as at 10 in Fig. 153, much morehighly magnified. You see the loop-like termination of thtjnervous fibrils. You can readily see that every vibration ofthe fluid would make an impression upon these nervous fibrilsthus distributed upon this delicate membrane, which has thefluid upon both sides of it. 424. The distribution of the nerve is after a different man-ner in the cochlea. Here there is no loose membrane, with thenerve distributed upon it, and the fluid each side of it, as inthe vestibule and the semi-circular canals. But the nerve isdistributed upon the division wall of the galleries in a verybeautiful manner. This is represented in Fig. 155, in which 2. is the nerve, and 3, 3, 3, show its distribution. These fibrilslie in little channels in a lamina, or leaf of solid bone. But thebone extends only to 4, 4, and the remainder of the divisionwall is made of membrane, represented at 5, 5, 5. At 7 is theopening in the cupola, by which the two spiral galleries com-municate. At 1 you have these parts of the natural size. Weknow not exactly how this mechanism works, but the proba-bility is, that the nerve receives impressions from the vibrationsof the fluid in two ways—directly from the fluid itself, and alsofrom the vibration of the membrane to which the extremitiesof the nerve are attached, this membrane being shaken ofcourse by the vibrating fluid. 425. Having thus described the parts of the organ of hear-ing, I will trace for you, with some particularity, the steps of 284 HUMAN PHYSIOLOGY. Steps of the process of hearing given in their order. the process of hearing, as it must occur in the case of everysound that produces that sensatio
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