CHAP, ii.] of Plants. Licbig. 529 



a purer and more definite form for the vegetable physiologists, 

 who turned their attention chiefly to the points mentioned 

 above. It is true that Liebig's work encountered lively opposi- 

 tion from these men also, and the two foremost representatives 

 of vegetable physiology at that time, Schleiden and von Mohl, 

 criticised it unsparingly ; this was due partly to the deductive 

 method adopted by Liebig, to which botanists were un- 

 accustomed in physiological questions, and partly to the 

 derogatory expressions in which he indulged against the 

 vegetable physiologists, whom he held responsible with the 

 botanists generally for all the absurdities connected with the 

 humus-theory. Von Mohl asked, and justly, whether de Saussure, 

 Davy, Carl Sprengel, Berzelius and Mulder, the real founders 

 of the theory, were botanists. But it was unnecessary for 

 von Mohl, Schleiden and others to feel touched by Liebig's 

 reproach, at least so far as it was addressed to professed 

 physiologists, for they were no more physiologists than Davy, 

 Berzelius or Mulder. Professed vegetable physioligists, official 

 public representatives of vegetable physiology there were none, 

 and then as now every one who occupied himself occasionally 

 with questions of the kind was called a vegetable physiologist. 

 In this way the contest became a dispute about words, and 

 Liebig, von Mohl and Schleiden lost an excellent opportunity 

 for influencing public opinion in favour of the idea, that it was 

 high time to establish public official representatives of so 

 important a branch of science, who should devote themselves 

 entirely to it ; how could it be expected that Professors of 

 botany, who were required by the government and the public 

 to work for the advancement of systematic botany, phytotomy, 

 and medical botany, to give instruction in these subjects, and 

 to devote a large portion of their time to the management of 

 botanic gardens, should do much to promote the study of 

 vegetable physiology, which demands very considerable 

 acquaintance also with physics and chemistry? and where 

 were the laboratories and the instruments for the serious 



M m 



