4 PREFACE 



confident will commend it to physicians, health officers and 

 public spirited citizens generally. In connection with the 

 different systems of organs, the nature and causes of com- 

 mon diseases are discussed in simple terms with such sug- 

 gestions about the prevention of disease as may help s to 

 make the high school student more intelligent in regard 

 to his own health and the health of the community. 



In the treatment of the problems of the physiological effects 

 of alcohol it is assumed that students using this book are of 

 an age to appreciate that some of the many problems con- 

 nected with the use of this drug are still unsettled. Hence, 

 while some aspects of this subject have been introduced with- 

 out anticipating any final conclusion, the attempt is made 

 to point out the most important of the evil effects resulting 

 from the use of this drug. 



The revised edition contains numerous additions to the 

 text embodying the results of the most recent scientific investi- 

 gations. Especial attention has been given the newer con- 

 ceptions of proteid digestion, carbon dioxid in respiration, 

 vitamines, the role of certain hormones, and the etiology of 

 numerous diseases. Since the last few years have offered 

 more convincing proof than ever before of the vital relation 

 between hygiene and health, sanitation and safety, especial 

 care has been taken to rewrite and to expand the chapter on 

 public control of health. The number of laboratory exercises 

 and demonstrations has been materially increased. These 

 have been assembled in a separate section and placed in the 

 back of the book with page reference to the portion of text 

 to which each applies. 



ROBERT A. BUDINGTON. 



