Mr. Everitt on separating Manganese a?id Iron. 193 



ject, M. Cauchy proceeds to show how the sum of terms in- 

 dicated by -5* may be changed into definite integrals. In this 

 investigation it will not be necessary to our purpose to follow 

 him, but we shall proceed to some remarks on the expressions 

 above deduced and their physical applications. 

 [To be continued.] 



XXXII. (Economical Meaiis of procuring pure the Salts of 

 Manganese^ and of analysing the Minerals 'mhich contain 

 Manganese and Iron^ S^c, By Thomas Everitt, Esq.,, Pro- 

 fessor of Chemistry to the Medico-Botanical Society, Sfc* 



TTAVING had occasion for some pounds of pure salts of 

 ^ manganese for experiments on dyeing, my attention was 

 turned to consider the convenience and oeconomy of those 

 processes prescribed in our systematic works. The process 

 of Faraday by hydrochlorate of ammonia, is easy of execu- 

 tion, and perfect as to the results, but expensive; that of 

 Turner, " by mixing the oxide left after procuring oxygen gas 

 by heat with one sixth of charcoal, and exposing to a white 

 heat for half an hour in a covered crucible, dissolving in 

 hydrochloric acid, evaporating to dryness, and keeping the 

 mass in perfect fusion for a quarter of an hour, &c." yields also 

 good results, but is tedious in the execution, and expensive, if 

 time and trouble be considered ; moreover, by the first igni- 

 tion, although we subsequently save a little hydrochloric 

 acid (none being lost as chlorine) by reducing the manganese 

 to protoxide, we also at the same time render the iron in such 

 a state that on dissolving in hydrochloric acid, we have a 

 protoxide, which is more difficult to get quit of by the second 

 ignition than it would have been as a peroxide. 



As I possessed a large quantity of hydrochlorate of man- 

 ganese and iron, the accumulated solutions from preparing 

 chlorine by hydrochloric acid and ordinary oxide of man- 

 ganese, I was induced to make a variety of trials on this li- 

 quid with the view of separating the iron from the man- 

 ganese ; the results of which trials being entirely satisfactory, 

 I venture to request a place for a short account of them in 

 the London and Edinburgh Philosophical Magazine. 



Method, No. I. — Depending on the circumstatice that when 

 a solution of hydrochlorate of iron, strictly peroxide (which is 

 always the case in the above liquid), is evaporated to dryfiess^ 

 and the heat afterwards slightly elevated, a small portion sub- 



* Communicated by the Author. 

 Third Series. Vol. 6. No. 33. March 1835. 2 C 



