306 



ANIMAL MECHANISM. 



contiguous buildings, to save a town, when they can no 

 longer master a threatening conflagration. ( 7 ) 



PARTIAL DEAFNESS, FROM A COLD. 



Probably, in a majority of cases, partial deafness arises 

 from a slight inflammation of the tube opening behind 

 the palate. In consequence of this, the balance between 

 the air in the tympanum and mouth, is destroyed, and 

 the regular vibratory function of the membrane is alter- 

 ed. A deafness in one ear generally depends on this 

 cause. Tumors in the throat, and polipi of the nose, 

 by pressure on the mouth of the eustachian tube, where 

 it opens back of the soft palatine arch, may each of 

 them be the cause of deafness. Deafness in fevers is 

 an excellent symptom, and offers encouragement in the 

 worst cases, because it is an evidence of a diminution of 

 the morbid condition of the brain. 



FIG. 10. 



Explanations to Figure 10. 

 An enlarged ivew of the labyrinth laid open. 



a> 5 f C) the cochlea. To exhibit the zona mollis ; the outside 



or bony case removed. 



(!) Painful affections of the ear may be induced from habitually 

 picking the ears, a very pernicious practice. In India, where a 

 cla*s of men particularly follow the profession of cleansing ears, cut- 



