ESSAY XXIV. 



SOME INCIDENTAL REMARKS ON THE AFFINITY OF 

 BODIES. 1 



THE few following observations on Mr. Wenzel's doctrine 

 of the affinity of bodies are not made with a view to 

 detract from his merit, but to show both my attention to 

 his valuable book, and how necessary it is to repeat the 

 experiments of others, when they do not coincide with 

 the principles of chemistry. 



P. 9. That metals dissolved in acids are unchanged, 

 and remain just in their former state, is contrary to all 

 experience in chemistry ; which shows that they lose their 

 inflammable principle during solution. 



P. 14. The position that salts do not act, unless in 

 solution, fails in many cases. When powdered chalk, for 

 instance, is boiled with Prussian blue, reduced likewise to 

 powder, the former attracts the colouring matter of the 

 latter, and yet chalk is insoluble in water. 



P. 40. Mr. Wenzel does not explain the decomposition 

 of vitriolated tartar right. For if the fixed alkalies had 



1 The name of the excellent Mr. Scheele, a German, and at present 

 settled as an apothecary at Koping, in Sweden, will serve as a sufficient 

 recommendation to all his productions. The present remarks, though 

 they have a reference only to Mr. Wenzel's Doctrine of the Affinity of 

 Bodies, bear, like all his other works, the stamp of acuteness and truth ; 

 and as they are delivered with proper candour, they rather do honour 

 to Mr. Wenzel, to whose merits I here subscribe my testimony. CRELL, 

 Ch&iti. Journ., Th. 4. 



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