IV 



tinental Philosophers, down to the close 

 of 1819- 



The chemical department has, in like 

 manner, undergone the careful revision 

 of a gentleman eminent in the science of 

 Chemistry. So numerous and important 

 have been the accessions to this region 

 of human knowledge, in the course of 

 the last twelve years, that a cautious 

 revision has, in fact, included the entire 

 re-composition of a considerable portion 

 of the second volume. 



The Proprietors have every reason to 

 believe that the improvements thus made 

 to the Lectures will considerably aug- 

 ment their utility : and they humbly yet 

 confidently anticipate the reward of an 

 enlightened public, for the expense they 

 have incurred by engaging gentlemen of 

 such acknowledged competence to make 

 the volumes exhibit a correct yet popu- 

 lar view of the present state of Experi- 

 mental and Chemical Philosophy. 



July, 1820. 



