PREFACE 



IN the following pages no attempt has been made to deal with 

 more than one part of the study of biological chemistry namely, 

 that concerned with the structure of materials of which the 

 bodies of living objects are composed. In many parts this book 

 does not differ markedly from an elementary text-book on organic 

 chemistry. Certain subjects, however such as, for example, the 

 aromatic derivatives have been dealt with very briefly, whereas 

 the treatment of other subjects such as the carbohydrates and 

 proteins, which are of great importance to the physiologist has 

 been expanded beyond the limits which are usual in an elemen- 

 tary text-book. Furthermore, an attempt has been made to 

 indicate the methods by means of which the branch of chemical 

 science known as organic chemistry may be applied to biological 

 research. 



It is hoped that a book in this form may, when the study of 

 it is supplemented by practical exercises carried out in the 

 laboratory, prove of use to students of medicine and of biology 

 generally. 



Other branches of biochemical investigation can only be 

 studied satisfactorily by those who possess a good fundamental 

 knowledge of physical chemistry; the discussion of them has 

 been entirely omitted from this book. 



471KJ. 



