4 Trans. Acad. Sci. of St. Louis 



Friederich Woeliler, then a teacher at the Gewerbe- 

 schule in Berlin, broke down this barrier; the first time 

 in the world's history a chemist had succeeded in making 

 an organic material named Urea from inorganic sub- 

 stances, and recognized the fact. Since that time an 

 almost inconceivable number of carbon compounds have 

 been construed and manufactured, part of which were 

 produced by nature in plants and organisms, and many 

 more of equal importance, which are not found in nature 

 but are made in chemical laboratories by men. From 

 the preparation of artificial Urea the manufacture of 

 organic chemical compounds has grown to enormous 

 dimensions, culminating in the development of our pres- 

 ent dyestuff industry and the manufacture of medicinal 

 chemicals, of perfumes, flavors and scents. 



But the study of organic compounds was taken up by 

 other and younger men, among whom A. W. v. Hofmann 

 (1818-1892) became famous as leader in the dyestuff in- 

 dustry. After splendid discoveries in the field of organic 

 chemistry, Woehler drifted back to research in the in- 

 organic field, where he had already been successful by 

 discovering a way of making metallic aluminium in 1827, 

 and in 1856 he discovered ** Adamantine Boron" in co- 

 operation with St. Claire Deville. Woehler 's life work 

 was in the field of inorganic chemistry, where he, through 

 his many followers, exerted great influence up to the end 

 of his life. Justus v. Liebig (1803-1873) was three years 

 younger than Woehler, but they met in 1825 and became 

 friends for life. The continuous interchange of ex- 

 perience was most fruitful, and is well known from their 

 published correspondence. But about 1838 Liebig began 

 to drift into chemistry of plant and animal life, and so 

 we find about the middle of the 19th century Woehler, 

 Hofmann, and Liebig as the great leaders in three fields; 

 inorganic chemistry, organic chemistry, and agricultural 

 chemistry. Under the guidance of these illustrious men 

 and many of their colleagues, the three fields of chemis- 

 try have been developed by their many followers into 



