TRANSLATOR'S PREFACE 



PROF. A. BLONDEL was the first writer to publish a systematic, 

 comprehensive work on Synchronous Motors; and his book, although 

 it has now been before the public several years, still remains the 

 leading work on that important subject. Owing to the non-existence 

 of an English edition, it is not, however, as well known and as much 

 appreciated as it deserves to be, by English-speaking readers. 



The translation of this celebrated, one might almost say classical, 

 work into English, was undertaken at the suggestion of teachers and 

 others who were desirious of making more extensive use of the work 

 than is possible if the French text alone is available. 



The author and the publisher both accepted 'the suggestion that 

 the scope and the usefulness of the book might be increased mate- 

 rially by including in it some reference to " Rotary Converters." 

 Excellent material for this purpose was already available in the form 

 of a paper presented by Prof. Blondel, at the Electrical Congress in 

 Paris, in 1900. Two other papers presented by him at the Electrical 

 Congress at St. Louis, in 1904, also were of sufficient interest in this 

 connection to make their reproduction desirable. 



It was decided to separate the contents of the book into three 

 distinct parts. Part 1, relating to Synchronous Motors, corresponds 

 to the original French work on Synchronous Motors. The author 

 himself corrected the French text, and he also supplemented it 

 with much new matter while the translation was in process. The 

 proofs of the English text were submitted to several persons who 

 were well qualified to criticise the text and suggest improvements 

 therein. The French text of Part I is also supplemented by an 

 additional chapter contributed by Prof. C. A. Adams, of Harvard 

 University. Part I may therefore be considered fairly well brought 

 up to date. Part II, relating to Synchronous or Rotary Converters, 

 is made up of old and new matter. The old matter (Chapters I 

 and II), constitutes a translation of Prof. Blondel's Paris-Congress 



