SYSTEMATIC SYNTHESIS OF TISSUES INTO ORGANS. 309 



approaches it in power to sway the mind. The persuasive 

 tones of eloquence through the ear exert more power to 

 stir or stay the passions of men than all the arguments 

 the ablest reasoner can address to the judgment. "Lend 

 me your ears," said the ancient orator ; and when his 

 hearers had done that, and they were filled with the be- 

 witching cadences of his voice, they were the unwitting 

 slaves .to his will. Yet as a physical organ of hearing 

 the ear is exceedingly simple : its wondrous power con- 

 sists in its nervous relations to the mind. 



FIG. 201. 



Fig. 201 is a beautiful view 

 of the Ear ; 1, external, 2, mid- 

 dle, 3, inner ear ; 13, a section 

 of the air-tube, which section 

 extends through the front of 

 2, and the middle of 19, a tube 

 called Eustachian, leading to 

 back part of nostril. If a per- 

 son close the nose and mouth, 

 and blow air from the lungs, 

 it will press through 19 into 

 2, and produce a sound. 14, 

 bottom of air-tube, a vibrato- 

 ry membrane through which 

 forceis determined ; 22, semi- 

 circularcanals, through which 

 quality is determined ; 24, co- 

 chlea, through which pitch is 

 determined ; 18, bones of ear. 



848. THE EAR is CONSTRUCTED in three parts, called 

 the external, middle, and internal ears. 



849. THE EXTERNAL EAR is CONSTRUCTED of the 

 auricle, or ear, and the meatus, or tube. 



850. THE AURICLE is CONSTRUCTED of a framework 

 of gristle and sinewy fibres covered with skin, in which 

 there is some fat and numerous oil-glands. 



Effect of -*>cal cadences ? Describe Fig. 201. 848. How is ? 849. How is ? 

 850. How is -? I 



