ORGANIC CHEMISTRY 



laboratory, but all attempts to obtain ' organic ' 

 compounds in this manner failed ; in fact, it was 

 supposed that in living nature elements obey 

 different laws from those obtaining in minerals. 

 The notion was evidently confirmed by the re- 

 markable difference in the chemical nature of the 

 substances met with in the two groups. This was 

 the position in 1827. By this time chemists had 

 come to the conclusion that it was highly improb- 

 able that they would ever succeed in imitating the 

 products of living nature. 



In the following year, however, two series 

 of experiments were made which opened a new 

 period in the science of organic chemistry. Alcohol 

 had hitherto been obtained only by the action of 

 the living organism of yeast on sugar a product 

 of vegetable origin ; but Hennell showed that it 

 could be made from ethylene, a gaseous compound 

 of carbon and hydrogen. Then Wohler succeeded 

 in obtaining urea by heating a solution of 

 ammonium cyanate. Urea had previously been 

 obtained only from the decomposition products of 

 the animal organism. The challenge which these 

 classical researches offered to the vitalistic con- 

 ception of organic chemistry was not fully recog- 

 nised at the time ; in fact, this view seems to have 

 persisted in more or less modified forms for another 

 quarter of a century. By that time the synthesis 

 of many substances occurring in nature had been 



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