22 Biography of Berzelius. 



at all in accordance with the electro-chemical views of Ber- 

 zelius, and that consequently these views were incorrect. 

 But when such a substitution takes place, it is, as already 

 mentioned, generally only in the compound radical, — that is, 

 the conjunct, and a new radical is thus formed, in which chlo- 

 rine may perhaps occupy the place of hydrogen, but cannot 

 play the same part as it did. Substitution of elements may 

 therefore be very satisfactorily explained, according to the 

 principles of Berzelius ; and if his theory be impartially com- 

 pared with the others which have been put forward in such 

 number in organic chemistry, the inference will be, that in 

 the present state of the science it is in a position to explain 

 the facts more satisfactorily than any other. 



On looking carefully through the various editions of this 

 work, it is impossible not to regard it with admiration. It 

 is not only the clear and comprehensive description which 

 attracts, — the sound, impartial criticism, which compels men 

 of opposite opinions to appreciate justly, — or the great mi- 

 nuteness which has not left unnoticed a single fact, however 

 trifling, if it was of any influence — but it is also the enor- 

 mous industry which must create astonishment. A scientific 

 man who had done nothing more than publish this excellent 

 work, in so many editions, each of which was so completely 

 revised that but little of the previous edition was retained, 

 could not be refused by us our grateful acknowledgments of 

 his great industry : and yet this constitutes but a fraction 

 of the achievements of Berzelius. 



It is touching to call to mind the words with which he 

 concluded the preface to the last German edition, which he 

 could not quite complete ; it is dated November 1842. He 

 says, " I cannot overlook that, even if the Almighty should 

 grant me life and power to complete the edition of which the 

 first part is now published, this will be the last. For this 

 reason, I considered it necessary to revise it so thoroughly, 

 that I could express the final views which have appeared to 

 me as the most probable during the long space of time in 

 which I was so fortunate as to be able to follow with unin- 

 terrupted attention the development of the science, from the 

 first growth of the antiphlogistic chemistry up to the present 



