PREFACE TO THE 8ECOND EDITION. v 



II and III have been revised by Dr. Dick in the 

 light of recent work and some of them largely or 

 wholly rewritten, notably those on "Syphilis" and 

 "Spotted Fever." As a result the size of the book 

 has been increased nearly 200 pages. It has been 

 the aim throughout to follow the lines laid down 

 by Dr. Eicketts in order to secure an adequate 

 presentation., suitable for physicians in general, 

 of the large subjects of infection and immunity 

 as illustrated by the human infectious diseases in 

 the light of modern knowledge. The present 

 intense and widely spread activity of investigation 

 in these fields, with its many discoveries, is giving 

 us new principles and methods of treatment, cura- 

 tive as well as preventive, and of diagnosis, which 

 require a thorough mastery by the physician in 

 order that they may be used to the best advantage. 

 It is my belief that this book by Dr. Eicketts as 

 revised and enlarged by himself and Dr. Dick will 

 be of real service to the physician who desires a 

 reliable guide to a helpful understanding of the 

 subjects with which it deals. May the use to 

 which it is put show that the labor expended on 

 it shall not have been in vain. 



LUDVIG HEKTOEN. 

 CHICAGO, Mav 5, 1911. 



