iv PREFACE. 



Handbuch der organischen Chemie (II. Auflage, Leipzig, 

 1886-1890) has been substantially followed. 



The illustrations, where the contrary is not expressly 

 stated, are prepared from the author's original drawings. 



The manuscript was practically completed in July, 1891 ; 

 but I have tried to include the more recent literature, so far 

 as possible, during the printing. 



March, 1892. 



