6 EDITOR'S PREFACE. 



elation of their helpfulness in the matter of producing the 

 proper character of work. 



In order to render the volumes suitable for quizzing, and 

 yet preserve the continuity of the text unbroken by the 

 interpolation of questions throughout the subject-matter, 

 which has heretofore been the design in books of this type, 

 all questions have been placed at the end of each chapter. 

 This new arrangement, it is hoped, will be convenient alike 

 to students and practitioners. 



VICTOR C. PEDERSEN. 



NEW YORK, 1903. 



