73 ACCOUNT OF BOOK9. 



Socquet on Ca- The 6th contains feven cafes of chemical affinity : — 1 . Pre* 

 ^ ,c " difpofing affinities, as they are called : 2. The decompofition 



of fulphate of iron by cauflic ammoniac : 3. The decompofi- 

 tion of muriate of foda by fulphate of magnefia, or of the zero 

 of Reaumur : 4. The reciprocal decompofition of alkaline 

 phofphates by carbon, and of alkaline carbonates by phofpho- 

 rus : 5. The decompofition of water in the folution of iron by 

 diluted fulphuric acid ; and the decompofition of the acid, not 

 of the water, in diffolving quickfilver by the fame menftruum ; 

 5. The precipitation of free fulphuric acid, by mixing the two 

 fulphates of mercury and ammoniac: 7. Whence comes it, 

 that thofe portions of folvents which are laft fixed in their 

 bafes eafily feparate from them, while the firfi portions, though 

 of the fame nature, and fixed in the fame fubflances, adhere 

 to them much more forcibly ? 



The author's refidence in Italy having given him an oppor- 

 tunity of travelling over almofl all the provinces of the quon- 

 dam ftate of Venice, and fome other countries dependent on 

 Auftria, he vifited a great number of productive and intereft- 

 ing manufactories. The extenfive alum mine of Souvignaco, 

 in Iftria, of which there was no description extant, probably 

 on account of its very remote and wild fituation, and perhaps 

 becaufe it is of no ancient date, afforded him fome curious 

 particulars refpecling the difpofition and nature of the ore, 

 the fimple, ingenious, and partly new procefles followed there, 

 and the theory of the various phenomena they exhibit. Thefe 

 are the fubjects of the 7 th effay. 



In the 8 th Dr. S. gives a fummary of his experiments on 

 the extraction of pure copper from bell-metal, the remits of 

 which had already been pubhfhed in feveral Italian jour- 

 nals ; together with fome other operations in the large way, 

 which he had executed at Venice on different objects of art, 

 particularly the feparation of foda from common fait *. The 

 corrections, or rather additions, propofed by the Chev. Napione 

 to the procefles already known for decompofing the different 

 kinds of bronze, were too interefting, for our author to omit 

 , making them known at large ; particularly as he had an op- 

 portunity of convincing himfelf of their utility, by repeating 

 the experiments of that learned mineralogift, at Turin* 



* See Opufcoli fcelti fulle Scienze efulle Arti : da Carlo Amoreti s 

 torn, xx, Milan, 



Atlas 



