^PREFACE. vii 



to the point of view of the physician, but to that 

 of the botanist, the general biologist, and the 

 chemist, and indeed to that of all those who 

 have a general interest in the progress of 

 modern science and who wish to inform them- 

 selves upon the practically important questions 

 of the day. 



Like all branches of theoretical and practical 

 medicine, bacteriology owes much of its early 

 advancement to the leaders of the Prussian 

 army medical department. The Prussian sur- 

 geon Struck, as head of the Imperial Board 

 of Health in Berlin, took the initiative in creat- 

 ing the first standard working laboratory, which 

 served as a model for all subsequent institutes ; 

 without this powerful aid Koch could not have 

 developed his pioneer methods. 



Earlier pupils of the army medical school, 

 like Helmholtz, Virchow, Reichert, Leyden, 

 Fischer, and Nothnagel had already achieved 

 important professional positions ; and upon the 

 establishment of hygienic and bacteriological 

 laboratories and the creation of professorships, 

 German army physicians, and chiefly indeed 

 those who were pupils of this institute, appeared 

 as workers of the first rank ; among these I may 

 name, Bshring, Buchner, Fischer, Gartner, 

 Gaffky, Loffier, R. Pfeiffer and Schroter. I 

 myself also have the honor to be a pupil of this 



