MARCEL NENCKI, 1847— 1901 513 



assistant in the Pathological Institute in Bern. Here he was 

 destined to remain for twenty years, and it was here that the 

 most considerable part of his life's work was carried out. 

 From such colleagues as Naunyn, Langhans, and Kocher he 

 received every encouragement and stimulation, and he rapidly 

 obtained the academic promotion he deserved. In 1877 a chair 

 of physiological chemistry was created for him. In 1891 he 

 was offered the direction of a laboratory at the newly created 

 Oldenburg Institute of experimental medicine at St. Petersburg, 

 and, attracted by the increased facilities in a splendidly 

 equipped laboratory, he reluctantly agreed to leave Bern. 

 Here he remained till his premature death from cancer in 

 1901. His association with Pawlow at St. Petersburg was 

 perhaps the most memorable incident of this later stage of 

 his career. 



To summarise Nencki's work is no easy task, for his versa- 

 tility, his skill as a chemist and his biological instinct, attracted 

 him to many fields of research, and his collected works fill two 

 large volumes, each containing more than eight hundred pages. 

 They comprise works on pure organic chemistry, on physio- 

 logical chemistry and pharmacology, and on bacteriology, the 

 latter subject treated from both the chemical and morphological 

 standpoints. It will be most convenient to consider first his 

 researches on pure chemistry, and the morphological aspects 

 of bacteriology, and to reserve the consideration of his physio- 

 logical chemical work to the last — for it is to his contributions 

 to this branch of science that he owes his principal title to fame. 



Organic Chemistry, etc. 



His first series of researches on organic chemistry were 

 devoted to the preparation of various new derivatives of 

 Thiurea, with the object of obtaining synthetically uric acid. 

 In this object he was not successful, although he obtained 

 many new derivatives of interest. He also prepared a large 

 series of new derivatives from the sulphocyanides. Closely 

 allied with urea and uric acid derivatives are those of guanidine, 

 and from this latter body, by condensation with fatty acids, 

 Nencki produced a series of crystalline products known as 

 the guanamines, of which the crystals have well-defined forms. 

 These guanamines Nencki often prepared subsequently for the 

 purpose of identifying the various fatty acids obtained by him 



