88 DISCOURSE ON THE STUDY 



teach us to limit our views to that of laws, and to 

 the analysis of complex phenomena by which they 

 are resolved into simpler ones, which, appearing to 

 us incapable of further analysis, we must consent 

 to regard as causes. Nor let any one complain of 

 this as a limitation of his faculties. We have here 

 " ample room and verge enough" for the full exer- 

 cise of all the powers we possess ; and, besides, it 

 does so happen, that we are actually able to trace 

 up a very large portion of the phenomen^ of the uni- 

 verse to this one cause, viz. the exertion of mecha- 

 nical force; indeed, so large a portion, that it has 

 been made a matter of speculation whether this is 

 not the only one that is capable of acting on material 

 beings. 



(79.) What we mean by the analysis of coihplex 

 phenomena into simpler ones, will best be under- 

 stood by an instance. Let us, therefore, take the 

 phenomenon of sound, and, by considering the 

 various cases in which sounds of all kinds are pro- 

 duced, we shall find that they all agree in these 

 points: 1st, The excitement of a motion in the 

 sounding body. 2dly, The communication of this 

 motion to the air or other intermedium which is 

 interposed between the sounding body and our 

 ears. 3dly, The propagation of such motion from 

 particle to particle of such intermedium in due 

 succession. 4thly, Its communication, from the par- 

 ticles of the intermedium adjacent to the ear, to 

 the ear itself. 5thly, Its conveyance in the ear, by a 

 certain mechanism, to the auditory nerves. 6thly,The 

 excitement of sensation. Now, in this analysis, we 

 perceive that two principal matters must be undei- 



