THE ROOTS OF EMPIRE 49 



inheritance. They tell us, with vast amplitude 

 of detail, of little and well-nigh purposeless wars, 

 of futile changes of dynasties, and so forth. They 

 give us "low gossip" concerning kings and queens, 

 but, of this momentous march of disease, which 

 has founded great empires, and for ever changed 

 the political face of the world, they tell us nothing. 

 Biologists and philosophers have expended vast learn- 

 ing and labour in tracing the evolution of hoof and 

 of horn. They are nearly all agreed that evolution 

 is caused solely by the elimination of the unfittest. 

 For thousands of years diseases due to micro- 

 organisms have been the main cause of human 

 elimination, and, therefore, of human evolution. 

 But on this great process and its tremendous 

 consequences, biologists are silent. Anthropologists 

 have carefully differentiated the races of mankind, 

 recording minute variations in size, shape, colour, 

 hair, and feature. But they have quite ignored 

 the most important of all human differences. 

 Medical men have a monumental literature on 

 disease as it affects the individual. On disease 

 as it affects the race they have published scarce 

 a volume. No theme more august could have 

 engaged the pen of any writer. They have 

 examined the individual as through a microscope ; 

 the race they have wholly neglected. 



The building of an empire is a great business. 



D 



