Il6 HISTORY OF CHEMISTRY. [LECTURE VII. 



ficially preparing any substance occurring in the organism : 

 but even this great step had not to be waited for much longer. 

 For this discovery we are indebted to Wohler, and with it he 

 opened his long and brilliant scientific career. 



Wohler had discovered cyanic acid in i822, 16 and was 

 occupied in its investigation when he made the observation, in 

 1828, that urea, a known product of animal life, was formed 

 upon the evaporation of a solution of its ammonium salt. 17 

 It is true that the problem was not completely solved by this 

 discovery. The synthesis from the elements was not yet 

 possible, but still the most essential thing had been accom- 

 plished. From inorganic compounds (amongst which many at 

 that time classed cyanic acid) 18 a substance had been prepared 

 which had hitherto been found in the animal organism only. 

 In spite of this, the revolution of ideas proceeded but slowly ; 

 it was still believed that the vital force could not be dispensed 

 with, and some decades afterwards, scientific discussions took 

 place as to its existence. Nowadays, when the materialistic 

 tendency becomes more and more ascendent, there are few to 

 be found who ascribe the production of organic substances 

 to forces different from those that govern the production of 

 mineral substances. It is true that the experimental science 

 has made great progress in this respect also, since it has 

 succeeded in preparing from their elements many organic sub- 

 stances. Thus Kolbe effected the complete synthesis of tri- 

 chloracetic acid, 19 and Berthelot the syntheses of formic acid 

 and of alcohol. The latter chemist inaugurated, with these 

 researches, his brilliant series of synthetical investigations. 20 



It may appear remarkable to many persons, into whose 

 hands a treatise on organic compounds published in the third 

 decade of this century, or earlier, may chance to fall, that 

 even at that time, when this department of chemistry was in 



16 Gilb. Ann. 71, 95. 17 Fogg. Ann. 12, 253 ; Quart. Journ. Science. 

 1828, 1, 491. 18 Compare, for example, Dumas, Traite. I, 409. 19 Annalen. 

 54, 145. 20 Berthelot, Chimie organique fondee sur la Synthese, Paris 

 (1860) ; see also his more recent investigations, Bull. Soc. Chim. [2] 7, 113, 

 124, 217, 274, 303, 310, etc. 



