170 Messrs. Mills and Bicket's Researches 



to precipitate the iron : the barium was separated by hydric 

 sulphate ; and the manganese was precipitated from the solu- 

 tion by means of sodic carbonate. The manganous carbonate 

 thus obtained was well washed with water, dissolved in hydric 

 chloride, and baric carbonate again added in order to precipi- 

 tate any remaining traces of iron. After the barium had been 

 removed with hydric sulphate, the manganese was again thrown 

 down as carbonate with sodic carbonate. The manganous car- 

 bonate, after being well washed and dried, was roasted : and the 

 oxide obtained was washed with dilute hydric nitrate to remove 

 any sodic salt. As the oxide obtained was very slightly acted 

 on by hydric sulphate at any temperature or of any strength. 

 we could not obtain the sulphate by the direct action of hydric 

 sulphate on this oxide. The oxide was therefore dissolved in 

 hydric chloride, the solution evaporated to dryness, and ignited 

 with excess of strong pure hydric sulphate. This ignition with 

 hydric sulphate having been repeated, the salt was found to be 

 free from all impurities, and quantitative analysis showed it to 

 be pure anhydrous manganous sulphate. 



The pure nickelous salt was prepared from a sample of 

 nickelous chloride which contained copper, lime, and iron, but 

 no cobalt. The copper present was precipitated with hydric 

 sulphide ; and the nickel in the filtrate was precipitated by 

 hydric oxalate in an acid solution. The nickelous oxalate was 

 washed thoroughly with dilute hydric nitrate, ignited, and the 

 oxide so obtained heated with pure hydric sulphate and ~o 

 converted into sulphate. 



The sodic carbonate was prepared by igniting hydrosodic 

 carbonate in a double platinum crucible, dissolving in water, 

 and reprecipitating with carbonic dioxide, igniting this as 

 before, and repeating the operation. The final precipitate was 

 dissolved in boiling water to the necessary strength. 



II. Method of separating Nickel from Manganese. 

 The method for the separation of manganese from nickel 

 that we found to give the most accurate results was that of 

 Beilstein and Jawein* for the separation of manganese from 

 iron. It consists in evaporating the mixed solutions to dry- 

 ness, adding strong pure hydric nitrate, heating to boiling, 

 and adding potassic chlorate in small quantities at a time. 

 The manganese is thus precipitated as pure black oxide; which, 

 after filtering and washing free from the nickel that is in solu- 

 tion, is dissolved in hydric chloride, precipitated with sodic 

 phosphate, and ignited and weighed as manganous pyrophos- 



* Leut. chem. Ges. Bet: 1679, p. 1528. 



