vi • Preface 



problems of poxiltry disease. Indeed even the veterinary 

 schools have given but scant attention to avian pathology. 

 Yet there exists, scattered in the literature, a large amount 

 of definite information regarding poultry diseases. It 

 was the purpose of the first edition of the circular on 

 which the present book is based to give a clear and rea- 

 sonably complete compilation and digest of the information 

 then existing in the literature regarding the commoner 

 diseases of poultry, their diagnosis, etiology, treatment, 

 and prognosis. 



The material was put together in the form which seemed 

 most likely to meet the needs of the practical poultryman. 

 It was soon found that in addition to this use, the book 

 was coming to be rather widely employed as a text.-book 

 for courses in the diseases of poultry in agricultural col- 

 leges and high schools. In preparing the present edition 

 the authors have kept more definitely in mind this second 

 way in which the book may prove useful, and have added 

 on that account some material not likely to be of imme- 

 diate interest to the poultryman. 



While none of the authors is engaged in researches in 

 pathology, it is a fact that they have all had extensive 

 experience in the appearance at autopsy of chickens dead 

 from some one or more of a very wide variety of causes. 

 There are but very few diseases mentioned in the book 

 with which the authors have not had first-hand experience. 

 It is hoped that the knowledge gained in this way will 

 prove to have been of some critical value in the compila- 

 tion of this book. 



