144 TERRESTRIAL ADAPTATIONS. 



we perceive that there are thousands of others, 

 and that we can only select a very small number 

 of those where the relation happens to be most 

 clearly made out or most easily explained. 



Now, in the list of the mathematical elements 

 of the universe which has just been given, why 

 have we such laws and such quantities as there 

 occur, and no other? For the most part, the 

 data there enumerated are independent of each 

 other, and might be altered separately, so far as 

 the mechanical conditions of the case are con- 

 cerned. Some of these data probably depend on 

 each other : thus the latent heat of aqueous va- 

 pour is perhaps connected with the difference of 

 the rate of expansion of water and of steam : but 

 all natural philosophers will, probably, agree, that 

 there must be, in this list, a great number of 

 things entirely without any mutual dependence, 

 as the year and the day, the expansion of air and 

 the expansion of steam. There are, therefore, it 

 appears, a number of things which, in the structure 

 of the world, might have been otherwise, and which 

 are what they are in consequence of choice or of 

 chance. We have already seen, in many of the 

 cases separately, how unlike chance every thing 

 looks: that substances, which might have existed 

 any how, so far as they themselves are concerned, 

 exist exactly in such a manner and measure as 

 they should, to secure the welfare of other things : 

 that the laws are tempered and fitted together 



