THE SCIENTIFIC SPIRIT IN GERMANY. 



191 



Twenty years after Gauss's great mathematical achieve- 

 ments, two new discoveries announced to the scientific 

 world that Germany had again taken a foremost position 

 in chemistry. These were Mitscherlich's discovery of 

 isomorphism in 1819, 1 and Wohler's preparation of an 

 organic compound from inorganic materials in 1828. 2 



In 1830 Liebig succeeded in finally establishing that 

 simple and accurate method of organic analysis known 

 by his name. Organic chemistry, in its modern sense, 



20. 



Liebig's 



The direction I had received in 

 Paris was a different one. ... I 

 saw very soon that all progress in 

 organic chemistry depended on its 

 simplification. . . . The first years 

 of my residence at Giessen were 

 almost exclusively devoted to the 

 improvement of organic analysis, 

 and with the first successes there 

 began at the small university an 

 activity such as the world had not 

 yet seen. ... A kindly fate had 

 brought together in Giessen the 

 most talented youths from all 

 countries of Europe. . . . Every 

 one was obliged to find his own 

 way for himself. . . . We worked 

 from dawn to the fall of night : 

 there were no recreations and 

 pleasures at Giessen. The only 

 complaints were those of the at- 

 tendant, who in the evenings, when 

 he had to clean, could not get the 

 workers to leave the laboratory." 

 See ' Deutsche Rundschau,' vol. Ixvi. 

 pp. 30-39. 



1 Eilhard Mitscherlich (1794- 

 1863), a pupil of Berzelius, dis- 

 covered in 1819 that in compound 

 bodies which crystallise in definite 

 forms certain elements can be re- 

 placed by others in the proportion 

 of their chemical equivalence with- 

 out changing the form of crystallisa- 

 tion. Such elements are termed 

 " isomorphous. " Berzelius declared 



this to be the most important dis- 

 covery that had been made since 

 the theory of chemical proportions 

 had been established. 



2 This synthesis was the prepara- 

 tion of urea, a highly organic sub- 

 stance, out of the compounds of 

 cyanogen, with the examination of 

 which he and Liebig were then oc- 

 cupied. " It was the first example 

 of the fact that an organic sub- 

 stance could, by chemical methods 

 alone, be produced out of inor- 

 ganic materials ; this discovery de- 

 stroyed the difference which was 

 then considered to exist between 

 organic and inorganic bodies viz., 

 that the former could only be 

 formed under the influence of vege- 

 table or animal vital forces, where- 

 as the latter could be artificially 

 produced " (Kopp, ' Geschichte der 

 Chemie,' vol. i. p. 442). It must 

 here be remarked that this state- 

 ment is only correct if the sub- 

 stances, cyanic acid and ammonia, 

 out of which Wbhler produced urea, 

 are considered to be inorganic ; in- 

 asmuch as neither of them had then 

 been produced otherwise than out 

 of organic substances, the popular 

 notion on Wohler's important dis- 

 covery requires this correction. See 

 Kopp, ' Gesch. der Wissenschaf ten 

 in Deutschland,' vol. x. p. 546. 



