The class-book of anatomy : designed for schools, explanatory of the first principles of human mechanism, as the basis of physical education . , canalsand pits we have been exhibiting. At some points, manydelicate threads are discoverable, side by side: at others,fibres are seen floating in the surrounding fluid, from themain trunk r at others, the nerve assumes the form of aflocculent paste, and at others, a woolly texture. Thewhole, distributed thus elaborately, constitutes the nerveof hearing. The sense of hearing is not confined, in a healthful con-dition of the organ, to any one particula
The class-book of anatomy : designed for schools, explanatory of the first principles of human mechanism, as the basis of physical education . , canalsand pits we have been exhibiting. At some points, manydelicate threads are discoverable, side by side: at others,fibres are seen floating in the surrounding fluid, from themain trunk r at others, the nerve assumes the form of aflocculent paste, and at others, a woolly texture. Thewhole, distributed thus elaborately, constitutes the nerveof hearing. The sense of hearing is not confined, in a healthful con-dition of the organ, to any one particular part or point:the sensation is perceived in the whole at the same instantof time. It has been recently demonstrated that the hu-man ear is so extremely sensible, as to be capable of ap-preciating sounds which arise from about 24,000 vibrationsin a second ; and, consequently, that it can hear a soundwhich lasts only the 24,000th part of a second. The ques-tion now may arise, why was it necessary to constructsuch an intricate machine, if one part of it has not a high-er office to sustain than another ? ANATOMICAL CLASS 79. 199. Explanation of Fig. enlarged view of the labyrinth laid open. a l: c the cochlea. To exhibit the zona mollis, the outside or bony case is , , — the too, — the semicircular /,, J, _ the posterior ; k, I, m,~the superior; o,p, q, the exterior 1 2 3 — the lamina, spiralis, seen on its under surface ; 3, the twosacsso often mentioned in this work, in the vestibule, which, view-ed in this plan, look like one. t u the membranous posterior canal. v\ J x _ the superior membranous canal, uniting with the last,at x v z tie exterior membranous canal. This diagram exhibits the distribution of the acoustic nerve in thelabyrinth • the large branch goes to the cochlea, and the three oth-ers, smaller, to the vestibule, and three semicircular canals. Economy was the object: — to pack as much as possiblein the sm
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Keywords: ., bookcentury1800, bookdecade1830, booksubjectanatomy, bookyear1834
