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Selected Articles. 
10 grains platina precipitated by zinc gave 0.42 cubic inches, 
10 " " " sugar 0.75 
10 by the method of E. Davy.* 1.10 
But, as the carbonic acid can only be the result of a greater 
oxygenation of the formic acid, the condition necessary to 
this oxygenation — the oxygen, must have been contained in 
the ethiops, hence this latter must be considered as an oxy- 
phorus. 
If the ethiops in this disoxygenated state be again moisten- 
ed with the acid and placed in oxygen gas, carbonic acid is 
produced, but more slowly ; and this production lasts, till all the 
formic acid is decomposed. The platina becomes charged 
with so much oxygen, that after drying it has its primary 
oxygenating properties. These facts prove that platina re- 
duced by the humid process is an oxyrrphoron, that is an ab- 
sorber of oxygen. 
Platina disoxygenized by formic acid has no action on hy- 
drogen gas, but in this opposite state absorbs this gas so ra- 
pidly, that it often becomes red hot. If this latter effect is 
not wished, and it is desired to ascertain the exact quantity 
of gas absorbed, the platina must be moistened with water. 
It will then be found, that it absorbs a volume of hydrogen, 
almost exactly corresponding to that of the carbonic acid, it 
had disengaged from the formic acid. 
10 grs. platina precipitated by zinc absorb about 0.42 cubic in. 
10 " " " sugar 0.75 
10 prepared by process, E. Davy 1.10 
It results from these facts, and from the action of platina 
on formic acid, that — 
10 grs precipitated by zinc contain 0.210 cubic inches oxygen. 
10 " " sugar 0.375 
10 process of E. Davy 0.550 
Or that if we assume, according to M. Liebig, the specific 
* By treating the deuto-sulphate of pla-tina with diluted alcohol 
