PREFACE TO THIRD EDITION 



Advantage has been taken of the exhaustion 

 of the last edition to correct a few typographical 

 errors and, at the suggestion of the authors, to 

 make slight changes in some of the articles. 



The remarkable sale of this work has made 

 necessary the third edition, within a year from 

 the date of its first publication. There are many 

 evidences that it has proven helpful to a large 

 number of veterinarians and that this edition 

 will meet with the cordial response given its 

 predecessors. 



The Editor. 



Chicago, March 1913. 



