CHEMICAL PRINCIPLES. 
365 
which, however, becomes black if its water of combination Oxides of pal- 
be separated from it. If healed in a glass, the muriate imme- 
dialely melts, and the heat may be raised to a slight degree of 
redness without decomposing it. By a stronger heat it is de- 
composed, and the metal is immediately reduced without one’s 
being able to discover any traces of a muriate of oxidule. 
Hence it appears that palladium has not any oxide analagous to 
the oxidum platinosum. If llio neutral muriate of palladium 
be dissolved in water, and then evaporated to dryness, it is in 
part decomposed, the water taking up the muriatic acid ; and 
on dissolving the dried mass, we have for a residuum a rose- 
coloured mass which is a submuriale of palladium. 
VIII. The oxides of Manganese. 
In an analysis of cast iron, published in the Afhandlingar i 
fysik, kemi och Mineralogie, 3 H. p. HI, I have described an 
experiment made for determining the composition of the 
oxidum manganicum, in which ItX) parts of metallic man- 
ganese being dissolved in the pure nitric acid, and the solu- 
ion evaporated to dryness, and decomposed by a red hear, 
there was produced 142,1 6 parts of black oxide. Dr. John 
obtained, by an experiment analogous with the above, 142 parts 
I of oxide. Dr. John analysed also a solution of the neutral 
I sulphate of manganese, in which there were lound, on pre- 
(cipitating with the muriate of barytes, 46,4a parts of oxidum 
manganosum. It produced 14S,5 parts of sulphate of barytes, 
equivalent to 50,03 parts of sulphuric acid. Now 100 parts of 
I sulphuric acid are neutralised by gi,2S parts of manganeous 
» oxide, and consequently, the Q 1, 28 parts of this oxide should 
• contain 19 ,Q 6 parts of oxigeu. In the manganeous oxide 
100 parts of the metal are therefore combined with 23 parts of 
to.xigen. But 42=28x15, and the manganic oxide should 
• contain one and a hall times as much oxigCn as is contained by 
Ithe manganeous oxide. Dr. John also found that 100 parts of 
I manganese oxidated by pure water, produced 115 parts of a 
green oxide, which combined with the liquid acids detaching 
hydrogen from them, and with the carbonic acid gas reducing 
a part 
