322 GREAT MEN OF SCIENCE 



new races, therefore do not arise by cross-breeding, the 

 only resuh of which is to produce a mosaic-hke combination 

 of quahties, governed by certain laws, which combination 

 may again fall apart. Suitably conducted selection by 

 breeding can again remove from hybrids inherited qualities 

 which are present, and can also again bring other qualities, 

 when they have once existed, into the race again. 



Mendel's results obtained by breeding experiments have 

 been shown to be in most significant agreement with the 

 results of microscopical investigation of the contents of the 

 body cells and sex cells of living creatures. In this way, the 

 study of the smallest living structure which can be seen under 

 the microscope, the cell nucleus - and perhaps also that of 

 the groups of atoms which compose it, and which cannot be 

 seen separately - may be brought into connection with the 

 study of the peculiarities of inheritance known to us in con- 

 nection with the great cell-states animated by a single spirit, 

 that is to say, the most highly developed living creatures, a 

 study already forming the science of race. This would 

 perhaps open up the possibility of approaching nearer to the 

 great question of how we are to imagine, in a more satis- 

 factory manner than has been possible since Darwin, and 

 especially since Mendel, the coming into exi.Uence of in- 

 heritable characteristics of an entirely new description, not 

 inherited from any ancestor, and yet transmissible, which 

 must certainly have occurred in the course of the upward de- 

 velopment of species upon earth. This question appears 

 to be one which it will not be possible to answer upon the 

 basis of the material world alone. 



But these distant goals again will only be approached by 

 natures of a kind as unprejudiced as Mendel. They will 

 have to be men of science capable of assimilating facts ot 

 every kind which have become known, and then working 

 them over like Darwin or Mendel, in seclusion, and adding 

 to them, their attention far removed from those 'isms' in 



