PREFACE TO THE SECOND EDITION. XI 



remark that he has found less occasion to introduce alterations or addi- 

 tions than might have been expected ; for the general doctrine respecting 

 the connection of the waste of the Organic structure with its functional 

 activity, and the dependence of the excreting processes upon the disin- 

 tegration of the bodily framework, which have been considered novel 

 features in the Animal Chemistry of Prof. Liebig, had been very clearly 

 set forth by himself. He cannot but think that the value of that able 

 Chemist's actual contributions to Physiological Science have been con- 

 siderably overrated ; though none can estimate more highly than he does, 

 the importance of the path of inquiry which Prof. L. has opened up. 



The only point in which any considerable fault has been found w r ith 

 this work, in the criticisms offered by the Medical Journals, has respect 

 to the arrangement of its subjects. It seems to be the general opinion 

 that the consideration of the Organic Functions should precede that of 

 the Functions of Animal Life, on account of the greater complexity of 

 the latter. The Author's reasons for the course he has adopted will be 

 found in 82 '; and he would only add here that the reader who is so 

 disposed will find no difficulty in passing at once from the General View 

 of the Functions (Chap. II.) to the Second Division of the book, com- 

 mencing with Chap. VIII.; deferring the consideration of the Nervous 

 System and its operations until the last. It is the Author's own opinion, 

 however, that this latter class of phenomena is, as now understood, the 

 least complex of the two. 



He has only further to notice, that a considerable number of new 

 Woodcuts, and a new Plate, have been added to the present Edition. 



Ripley, Surrey, Sept. 21th, 1844. 



