PBEFACE 



TO THE 



ENGLISH TRANSLATION 



IN presenting to the scientific world an English translation of 

 the text-book of Chemistry written by the great master of the 

 Periodic Law, we feel that no apology is necessary, for it was in 

 preparing the first edition of this book that the author was led to 

 those considerations which resulted in the discovery of that law, 

 and, moreover, the book is quite unique in its treatment of its 

 subject. 



In order to convey as nearly and clearly as possible the exact 

 meaning of the author, it has been our endeavour to give, as far as 

 the genius of the two languages permits, a literal rendering of the 

 original work. Some exception may no doubt be taken to some of 

 the sentences, but it was felt on the whole that it would be better 

 to have some inelegance of language rather than to risk the loss 

 of the exact shade of meaning that the author had intended to 

 convey. 



We have not considered ourselves at liberty to make any 

 alterations in the matter of the work, save the omission of two 

 notes referring to the meaning of Russian words, and of some 

 details referring to the waters of the streams near St. Petersburg, 

 which required local knowledge to be of any utility. It has, 

 however, been necessary to make a considerable change in the 



