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XTV. Experiments made for the Purpose of ascertdinhi(f 

 whether there he a real Acid rf Coh alt ; or, in other IVords, 

 whether Cobalt actually iniites with Oxygen to the Degree 

 nccesshry for Acidfication. By C. F. Bucholz *. 



INo newly discovered substance has been admitted more 

 readily^ and with less examination into chemical works, than 

 the supposed cobaltic acid of Brugnatelli, thoutih the expe- 

 riments from which its existence is concluded were verv 

 imperfect and unsatisfactory. As there are several metallic 

 acids, it was natural to conclude, by analogy, from these 

 experiments, that the existence of the cubaitic acid was real 

 or possible : but the defective nature of the experiments, 

 and the importance of the object, ought to have induced 

 themists to subject them to a strict proof; for the truth of 

 any circumstance can be proved only by the coincidence of 

 repeated experiments made to ascertain it. 



Convinced of the truth of this observation, and of the 

 incompleteness and inaccuracy of Bragnatelli's experiments, 

 and of the consequences deduced from them in regard to 

 the cobaltic acid, I undertook some new ones for the pur- 

 pose of examining them, and thereby ascertaining whether 

 there really be such a substance as cobaltic acid. In con- 

 sequence of the v.el! known impurity of zaftcr or gfay oxide 

 of cobalt, which, besides the so called oxide of Cobalt, con- 

 tains arsenical cobalt (perhaps arseaiate of cobalt), iron, 

 nickel, lime, siliceous earth, and other foreign matters, I 

 did not think it proper to repeat with it Brugnatelli's expe- 

 riments, as I had been taught by other experiments, which 

 will be mentioned hereafter, that the phaenomena observed 

 by Brugnatelli in the experiments he made with zall'er to 

 produce cobaltic acid, ought in all probability to be ascribed 

 to the arsenical acid of the zatl(.'r. I therefore resolved to 

 begin my experiments by a direct union of pure cobalt with 

 the oxvgen of oxvgenous bodies ; and I had the stronger 

 hopes of a favourable result, if the cobalt was susceptible of 

 this transformation, as I knew from the analogy of other 

 metals susceptible of acquiring the acid state, such as 

 chrome, schecl, molybdena, and arsenic, that the conver- 

 iJion of such metal into acids is exceedingly easy; One ex- 

 periment however, by M. Fiedler of Cassel, on the forma- 



* Frcm Scheier's AUgtmeines Jwrnal der Cbcniit, No. 51. 



toi.. tNWl. N«. 70. ^ tioj^ 



March lb04, 



