Scientific amusements . The ear (external) is composed of the auricle, thevisible ear, the auditory canal, and the drum-head, ormembrana tympani. The tympanum, or drum, is situatedbetween the external and the internal portions of the part is the middle ear, and is an air cavity, andthrough it pass two nerves, one to the face and the otherto the tongue. The internal ear is called the labyrinth,from its intricate structure. We give an illustration of theauditory apparatus of man. The auricle, or exterior ear, is also represented, but weneed not go into any minute description of the part
Scientific amusements . The ear (external) is composed of the auricle, thevisible ear, the auditory canal, and the drum-head, ormembrana tympani. The tympanum, or drum, is situatedbetween the external and the internal portions of the part is the middle ear, and is an air cavity, andthrough it pass two nerves, one to the face and the otherto the tongue. The internal ear is called the labyrinth,from its intricate structure. We give an illustration of theauditory apparatus of man. The auricle, or exterior ear, is also represented, but weneed not go into any minute description of the parts. Wewill just name them. Sound is the motion imparted to * auditory nerve, I50 SOUND. and we shall see in a moment how sound is undulations enter the auditory canal, having beentaken up by the auricle ; the waves or vibrations move atthe rate of i,ioo feet a second, and reach the drum-head,which has motion imparted to it. This motion or oscilla-tion is imparted to other portions, and through the liquid. I. Temple bone. 2. Outer surface of temple. 3. Upper wall of bony partof hearing canal. 4. Ligature holding hammer bone to roof of drumcavity. 5. Roof to drum cavity. 6. Semi-circular canals. 7. Anvilbone. 8. Hammer bone. 9. Stirrup bone. 10. Cochlea. 11. Drum-head cut across. 12. Isthmus of Eustachian tube. 13. Mouth of tubein the throat. 14. Auditor^canal. 15. Lower wall of canal. 16. Lowerwall of cartilaginous part of canal. 17. Wax glands. 18. Upper wall of cartilaginous portion of canal. 20. Mouth of auditorycanal. 21. Anti-tragus. in the labyrinth. The impressions of the sound wave areconveyed to the nerve, and this perception of the move-ment in the water of the labyrinth by the nerve threadsand the brain causes what we term hearing. Let us now endeavour to explain what sound is, andhow it arises. There are some curious parallels betweensound and light. When speaking of light we mentioned MUSIC AND NOISE. 15 I some of the analogies between sou
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Keywords: ., bookcentury1800, bookdecade189, booksubjectscientificrecreations
