CHAP. II. CHEMICAL PROCESSES. 381 



duced to the following: distillation, combustion, the 

 action of water, the action of acids and alkalies, the 

 action of oils and alcohols, and lastly fermentation. 

 They are much more intricate in their nature than 

 the mechanical processes, as well as more difficult 

 in their application. Their accuracy, which must at Originally 

 all times have depended upon the state of chemical ^ 

 knowledge, could not at an early period have been 

 very great. And accordingly we find that the prin- 

 cipal error of the earlier analysists arose chiefly 

 from the defects of their chemical processes ; as 

 well as from a mistaken notion, by which they fan- 

 cied that all the substances they obtained during the 

 analysis had previously existed in the vegetable ; 

 while the fact was, that many of them were entirely 

 the production of the process adopted. But the 

 errors into which experimenters were thus unfortu- 

 nately led began at length to be suspected ; because 

 similar substances were obtained from vegetables 

 possessing totally different qualities ; which mortify- 

 ing fact seems to have repressed for a time the ar- 

 dour of experimental inquiry, till at length new 

 adventurers arose, who, by exhibiting new views of 

 the subject, and introducing new modes of analysis, 

 enlarged the boundaries of science, and converted 

 even the disappointments of former analysists to 

 their advantage. Boulduc, Herman, and Cartheu- Improved 

 ser, may be mentioned among the first of the new Deduction 

 and more accurate experimenters in the field of 

 vegetable analysis, who were succeeded by Beccaria 



3 



