corresponding very closely to a composition MnO·5MnO₂, in which the calculated ratio is
1.200 : 1.000
Six month later (April 20, 1893) an analysis of the same material showed a ratio of manganese to available oxygen of
1.300 : 1.000
This result was confirmed Mʳ Walker who made repeated analyses of the substance at the same time.
Another sample of manganese oxide was prepared in the same manner as that used in the previous experiments and placed under water. An analysis made after
| Eight | days | gave | a | ratio | of | Mn : | available | O | = 1.013 : 1.000 |
| Twenty | ” | ” | ” | ” | ” | ” | ” | ” | = 1.037 : 1.000 |
| Forty three | ” | ” | ” | ” | ” | ” | ” | ” | = 1.040 : 1.000 |
The results here recorded clearly indicate that the brown oxide of manganese which is prepared by the reduction of potassium permanganate by manganese sulphate undergoes a spontaneous decomposition involving a loss of oxygen. This loss of oxygen or the effect of varying conditions upon this decomposition of manganese dioxide is now being investigated by Mʳ Walker of this laboratory.