PREFACE 



The development of chemical science in the last 

 thirty years shows a steadily increasing tendency to 

 elucidate the nature and reactions of substances pro- 

 duced by living organisms. The problem has been 

 attacked in two different ways, firstly, by the aid of 

 the highly developed synthetic methods of organic 

 chemistry — it will be enough to mention the brilliant 

 work of Emil Fischer, Kossel, and their pupils — 

 and secondly, by the powerful technical means 

 afforded by the modern development of physical 

 chemistry. The studies founded on the methods of 

 organic chemistry aim at investigating the structural 

 composition of the molecules of the chief products of 

 organic origin and subsequently building them up 

 synthetically. The physico-chemical methods, on 

 the other hand, give an insight into the nature of the 

 chemical processes which play an important role in 

 the living world. The work of organic chemists in 

 this region has been generally recognized as being 

 of high scientific interest, but the same cannot be 

 said regarding the work of physical chemists in the 

 domain of physiological chemistry. It may be 

 enough to cite one of the least aggressive utterances, 



