AUTHOR'S PREFACE. 



THE addresses which have been collected for the 

 first time in this volume and which were delivered in 

 the main as summaries of my own special investigations 

 concern themselves with the application of physical 

 chemistry to different fields in medicine as rendered 

 possible more particularly through advances in the 

 physics and chemistry of organic colloids. In that 

 questions in physiology as well as pathology and 

 pharmacology are touched upon, it may perhaps be 

 hoped that different circles of medical men may be 

 interested in the problems discussed in this volume. 

 The translated addresses differ in only a few unimpor- 

 tant abbreviations from the original. The development 

 of the guiding thought common to all of them stands 

 out quite clearly. Its foundation is the extensive 

 parallelism between the laws which govern changes in 

 the colloidal state in vitro and in the living organism. 

 Even though the future may become acquainted with 

 many a new fact through which the questions discussed 

 in this volume may be made to appear in a different 

 light, it will scarcely be possible to belittle the fruitful- 

 ness of the methods described and the stimulating effect 



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