LIEBIG 95 



^ In 1840 (ever-memorable year), while at Giessen, 

 Liebig published his famous and epoch-making work on 

 agricultural chemistry, Die organische Chemie in ihrer 

 Anwendung auf Agricultur und Physiologic. Although 

 Davy, thirty years before, had published a work on Agri- 

 cultural Chemistry, it was not until Liebig's book made 

 its appearance that any great stride was made in the 

 scientific principles of agriculture. This book is one of 

 those few works which stand out from all others on the 

 subjects of which they treat. It is undoubtedly the most 

 important work on agriculture ever given to the world as 

 the result of one man's researches and ideas. From the 

 land of Kant, Fichte, Schelling, Schiller, and other philo- 

 sophers, it is not surprising that we have such a far- 

 reaching and philosophic work as Liebig's Die organische 

 Chemie given to us. 



That an increase of solubility in bones and other 

 phosphates would be attended by an increased productive 

 power in the crop, was the idea of Liebig. He, in 1840, 

 recommended, in lieu of bones, the use of the substance 

 long well known to chemists as the acid or superphosphate 

 of lime, which is producible from bones and other phos- 

 phates by the action of oil of vitriol or sulphuric acid. 

 Practice has since shown the great advantage of Liebig's 

 suggestion. 



The chief point of Liebig's famous book was to show 

 that the humus of the soil is powerless to build up com- 



