PREFACE TO FOURTH EDITION 



IN preparing this revision the majority of changes have 

 been of details, the chapters and general arrangement of the 

 book have been kept as in the third edition. A number of 

 new illustrations have been added and others have been re- 

 engraved. Every effort has been made to bring the subject 

 matter up to date and to keep the book up to the highest 

 standard in every way. 



We appreciate the reception which has been accorded the 

 previous editions and hope that this will prove even more 

 valuable to the student and practitioner than those which 



have preceded it. 



EDWARD G. JONES. 



ALLEN H. BUNCB. 

 ATLANTA, GA. 



vn 



