THE RISE OF PHYSIOLOGY 185 



They change the whole aspect of the field in which they work, 

 and all later growth is influenced by their labors." Johannes 

 Muller was a man of very unusual talent and attainments, 

 the possessor of a master mind. Some have said, and not 

 without reason, that there was something supernatural about 

 Muller, for his whole appearance bore the stamp of the un- 

 common. His portrait, with its massive head above the broad 

 shoulders, is shown in Fig. 56. In his lectures his manner 

 and his gestures reminded one of a Catholic priest. Early in 

 his life, before the disposition to devote himself to science 

 became so overwhelming, he thought of entering the priest- 

 hood, and there clung to him all his life some marks of 

 the holy profession. In his highly intellectual face we find 

 "a trace of severity in his mouth and compressed lips, with 

 the expression of most earnest thought on his brow and eyi 

 and with the * mernb ranee of a finished work in every 

 wrinkle of hi fnten ." 



This extraoidinary man exercised a profound influence 

 upon those who came into contact with him. He excited 

 almost unbounded enthusiasm and great veneration anions 

 his students. f hey .were allowed to work close by his side 

 and so magnetic was his personality that he stimulated them 

 powerfully and succeeded in transmitting to them some 

 of his own mental qualities. As professor of physiology in 

 Berlin, Muller trained many gifted young men, among whom 

 were Briicke (181 9-1892), Du Bois-Rcymond (1818-1896), 

 and Hclmholtz (1821-1894), who became distinguished 

 scholars and professors in German universities. Helmholtz, 

 speaking of Muller's influence on students, paid this tribute 

 to the grandeur of his teacher: "Whoever comes into contact 

 with men of the first rank has an altered scale of values in life. 

 Such intellectual contact is the most interesting event that 

 life can offer." 



The particular service of Johannes M tiller to science was 



