REPORTS 



ON 



THE STATE OF SCIENCE. 



Preliminary Report on the Recent Progress and Present State of Or- 

 ganic Chemistry. By George C. Foster, B.A., F.C.S., Late As- 

 sistant in the Laboratory of University College, London. 



The late Mr. J. F. W. Johnston presented to the Second Meeting of this 

 Association, held at Oxford in 1852, a " Report on the Recent Progress and 

 Present State of Chemical Science." This Report included both Organic and 

 Inorganic Chemistry, but no subsequent Report exists in which the progress 

 of Organic Chemistry, as a whole, is discussed. It therefore seemed advi- 

 sable to take the year 1832 as the starting-point of the Report, the preparation 

 of which was entrusted to Dr.Odling and myself, at the Meeting in Leeds 

 last year. On commencing the task, we found that a satisfactory account of 

 the progress of organic chemistry, since that date, would be little else than 

 a tolerably complete history of that branch of science. Believing that such 

 a historical account would be of great value, we made some progress in 

 its preparation. Those, however, who have the greatest acquaintance with 

 the subject, will be the readiest to believe that it was utterly impossible for 

 us to bring such a Report to anything like a state of completeness in time for 

 the present Meeting. We thought, however, that such a general preliminary 

 account as we might be able to give, of some of the most recent discoveries, 

 illustrating some of the ideas most lately introduced into the science, might 

 perhaps have both interest and utility. 



In the following pages, therefore, in which such a general account is at- 

 tempted, historical completeness has not been aimed at ; the object has been 

 rather to place in a clear light the real nature and tendency of some of the 

 most important theoretical views which are now taking a place in the science. 



The reconciling of the theory of types with the theory of compound radi- 

 cles, which resulted from the discovery of the compound ammonias by Wurtz 

 and Hofmann, and the discovery of the mixed ethers (or ethers containing 

 two distinct alcohol-radicles) by Williamson, prepared the way for Gerhardt's 

 classification of chemical substances according to types of double decompo- 

 sition. The system of ideas, of which we may regard this classification as 

 an epitome, has exerted so great an influence on the progress of theoretical 

 chemistry during the last seven or eight years, that it becomes an essential 

 part of a survey like the present to cousider what parts of it have been 

 modified or confirmed by recent discoveries. 



1859. „ b 



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