NATURAL THEOLOGY. 



47 



of connected parts constitutes together an appara- 

 tus plainly enough relative to the trasmission of 

 sound, or of the impulses received from sound, and 

 only to be lamented in not being better under- 

 stood. 



The communication within, formed by the small 

 bones of the ear, is, to look upon, more like what 

 we are accustomed to call machinery, than any 

 thing I am acquainted with in animal bodies. It 

 seems evidently designed to continue towards the 

 sensorium the tremulous motions which are ex- 

 cited in the membrane of the tympanum, or what 

 is better known by the name of the " drum of the 

 ear." The compages of bones consists of four, 



[This figure represents the bones which form 

 the chain.] 



which are so disposed, and so hinge upon one an- 

 other, as that if the membrane, the drum of the 

 ear, vibrate, all the four are put in motion toge- 



