LAW; — ITS DEFINITIONS. 107 



say, what we do know is the Purpose. What we 

 do not know, and have no idea of, is how it was 

 made. That is to say, what we do not know is 

 the Law, the Force or Forces which have been used 

 as the instrument of that Purpose. When Man 

 makes a voltaic battery, he selects materials which 

 have properties and relations with each other pre- 

 viously ascertained — metals worked out of natural 

 ores, acids distilled out of other natural sub- 

 stances ; and he puts these together in such 

 fashion as he knows will generate the mysterious 

 Force which he desires to evoke and to employ. 

 But how can such a machine be made out of the 

 tissues of a fish ? W T ell may Mr Darwin say, " It 

 is impossible to conceive by what steps these won- 

 drous organs have been produced/' * We see the 

 Purpose — that a special apparatus should be pre- 

 pared, and we see that it is effected by the produc- 

 tion of the machine required ; but we have not the 

 remotest notion of the means employed. Yet we 

 can see so much as this, that here again other 

 laws, belonging altogether to another department 

 of Nature — laws of organic growth — are made sub- 

 * Origin of Species, p. 192, fust edition. 



