AUTHOR'S PREFACE. 



NOTWITHSTANDING my earnest desire to include the whole 

 of my materials in the present volume, I have been compelled to 

 devote it exclusively to the Animal Juices, and to postpone the 

 chemistry of the animal tissues and organs, and the consideration 

 of the zoo-chemical processes, to a third volume. In discussing 

 the chemical characters and the composition of the animal tissues, 

 I shall include the recent investigations regarding the paren- 

 chymatous fluids of the animal body. Liebig's examination of 

 the juice of flesh has afforded an admirable model, which has 

 already stimulated other chemists to pursue similar courses of 

 inquiry. The third and concluding volume, which will appear in 

 the course of the present year, will embrace Histo-Chemistry and 

 Zoo-Chemical Processes generally, with especial reference to 

 Digestion, Respiration, and Nutrition. 



LEIPSIC, 



July, 1850. 



.84605 



