ANTHROPOLOGICAL SOCIETY. 95 



to the development of higher forms of life, including human life, 

 and as such it performs the office of an efficient and not a final cause. 

 Since the close of the sixteenth century, when coal began to come 

 into general use as fuel, it may have also produced a new effect 

 upon the development of the race by greatly enhancing their 

 comfort and consequent efficiency for action. In so far the 

 correlation between the existence of the coal measures and the 

 advancement of man has a causal relation and constitutes a case of 

 adaptation ; in any other sense it must be regarded as a pure 

 coincidence. 



6. Very similar to this case is that of the late appearance, 

 geologically speaking, of the most important economic families of 

 plants, and particularly the Rosacea and Graminece. These plants 

 were shown to have been, equally with the coal measures, a condi- 

 tion to the existence of the higher forms of animal life which have 

 been genetically adapted to them. Considered from any other 

 point of view the co-existence is purely accidental. 



Under the second group, or that of pure coincidences, the 

 following cases were noted : 



i. The alleged advantage to man of the spheroidal form of the 

 earth in preventing irregularities in its motions, due to mountains 

 and other inequalities of its surface, which the equatorial meniscus 

 neutralizes. This, Kant, who first suggested it, proposed to explain 

 on teleological principles, and he rebukes the attempt to explain it 

 as due to the equilibrium necessarily produced by the formerly 

 fluid mass of the rotating planet. But as the mechanical explana- 

 tion is complete without the teleological one, and will apply to any 

 case, even where it might be a disadvantage, the latter is at least 

 unnecessary. 



2. The fact that there is no relation of dependence between the 

 dispersive and refractive powers of different substances, and which 

 alone renders the construction of the achromatic lens possible. 

 This was mentioned as a most fortunate case under the present head ; 

 but it was questioned whether this were not rather to have been 



