the hydrate of osmium trioxide, OsO3 •H.O or HaOsO4. Osmic acid is thus formed by the direct action of water, under the influence of sunlight and slight rise of temperature, upon the potassium salt.

Osmium Tetroxide (OsO4), a severe oxidizer, is highly poisonous even at low exposure levels. It must be handled with appropriate precautions. In particular, inhalation at concentrations well below ...