MANGANESE. 369 



Thus it appears, that 45 protoxide of manga- 

 nese become 50 deutoxide ; or, 4*5 protoxide 

 become 5 deutoxide : but 4 *5 is the atomic 

 weight of protoxide of manganese, and it con- 

 tains 1 atom of oxygen. Five, therefore, must 

 be the atomic weight of deutoxide ; and it is ob- 

 viously a compound of 



1 atom manganese 3-5 

 Ji atom oxygen 1*5 



5-0 



It is, therefore, similar in its composition to the 

 peroxide of iron. As its colour is either a brown- 

 ish black, or a shining black, according to the 

 mode of preparing it, we cannot with propriety 

 distinguish it by its colour ; and shall, therefore, 

 henceforth give it the name of deutoxide of man- 

 ganese. 



5. The composition of deutoxide of manga- 



perhaps 4-83; showing that it is still partly in the state of protoxide. This 

 is the oxydum mcmganoso-manganicum of Arfwedson, which he considers 

 as composed of 



1 atom protoxide 4-5 



:2 atoms deutoxide 10 



3)14-5 



4-8333 = atomic weight of the 



compound. 



When the black oxide is exposed to too high a temperature, it becomes 

 analogous to this in its composition, showing that it is partly converted 

 into protoxide. 



VOL. I. A a 



