FRANCIS GALTON 29 



contribute one quarter, and so on. He illustrates 

 this by calculating how much Norman blood a man 

 has who descends from a Baron of William the 

 Conqueror's. Assuming that the Baron weighed 

 14 stone, his descendant's share in him is repre- 

 sented by yo grain. 1 



This side of Galton's work is, in the judgment of 

 many, his greatest claim to distinction as a master 

 in the science of heredity. How far this is so I 

 shall not attempt to pronounce. It is possibly still 

 too soon to do so. Nevertheless, it seems to me 

 that Mendelism, the main facts of which are no 

 longer in dispute, will compel the world (if it has 

 not already done so) to look at variation in a very 

 different way to that of Galton. The Mendelian 

 does not, and never will, look at variation merely 

 as a "deviation expressed in statistical units." 

 Nor can he accept the ancestral law, because 

 he has convinced himself that some ancestors 

 contribute nothing in regard to certain charac- 

 ters. 



The contrast between Galtonism and Mendelism 

 may be illustrated by an example, which, if not a 

 strict analogy, has in it something illuminating, 

 especially for those who do not know too much of 

 the subject. Galton seems to me like a mediaeval 

 chemist, while Mendel is a modern one. Galton 

 can observe, or can follow the changes that occur 

 when two compounds are mixed. But he knows 

 nothing of the mechanism of what occurs. But 

 the Mendelian is like a modern chemist who calls 



^ Macmillan's Magazine, xii., p. 327. 



