50 



PART I. 



THE MECHANICAL FUNCTIONS. 



Chapter I. 



ORGANIC MECHANISM. 



'^. 1 . Organization in General. 



Life, which consists of a continued series of actions 

 directed to particular purposes, cannot be carried 

 on but by the instrumentality of those peculiar and 

 elaborate structures and combinations of material 

 particles which constitute organization. All these 

 arrangements, both as respects the mechanical con- 

 figuration and the chemical constitution of the ele- 

 ments of which the organized body is composed, 

 even when apparently most simple, are, in reality, 

 complex and artificial in the highest possible de- 

 gree. Let us take as a specimen the crystalline 

 lens, or hard central part, of the eye of a cod fish, 

 which is a perfectly transparent, and to all appear- 

 ance homogeneous, spherule. No one, unaccus- 

 tomed to explore the wonders of nature, would sus- 

 pect that so simple a body, which he might sup- 

 pose to be formed of a uniform material cast in a 

 mould, would disclose, when examined under a 

 powerful microscope, and with the skill of a Brew- 



