Vlll PREFACE TO THE SECOND EDITION. 



with the chapters, and in chronological order, may 

 be useful to those seeking further details. No 

 doubt Professor Baumgarten's Jakresbericht, the 

 first number of which has been issued this year, 

 will be found a valuable guide to current literature 

 in the future. 



The author desires again to express his ac- 

 knowledgments to Professor Gerald Yeo and 

 Mr. Herroun, of King's College, London. 



EDGAR M. CROOKSHANK. 



24, MANCHESTER SQUARE, W., 

 December, 1886. 



