DEDICATION. Vll 



he has received in the various branches of medicine ; 

 and his intimate acquaintance with the German 

 language — all these, taken together, are the best 

 securities that the translation is such as to convey 

 the exact sense of the original ; securities, such as 

 are not often united in the same individual. 



It is my intention to follow this second part witli 

 a third, the completion of which, however, cannot 

 be looked for before the lapse of two years. This 

 third part will contain an investigation of the food 

 of man and animals, the analysis of all articles of 

 diet, and the study of the changes which the raw 

 food undergoes in its preparation ; as, for example, 

 in fermentation (bread), baking, roasting, boiling, &c. 

 Already, it is true, many analyses have been made 

 for the proposed work ; but the number of objects 

 of investigation is exceedingly large, and in order 

 to determine with accuracy the absolute value of 

 seed, or of flour, or of a species of fodder, &c., as 

 food, the ultimate analvsis alone is not sufficient ; 

 there are required comparative investigations, which 

 present very great difficulties. 



Dr. JUSTUS LIEBIG, 



GlESSEN, 



drd June, 1842. 



