Acertain amount of sodium hyposulfite
([Na.sub.2][S.sub.2][O.sub.3] x 5[H.sub.2]O) and zinc acetate ([(C[H.sub.3]COO).sub.2]Zn x 2[H.sub.2]O) were dissolved in distilled water.
A more lasting solution to image fixing resulted from the observation made by the astronomer Sir John Herschel (1792-1871) that sodium hyposulfite
(thiosulfate) had silver-dissolving properties.
Asahi's "Super [H.sub.2]O." Asahi says the beverage has S[O.sub.2-], also called hyposulfite
. In solution, this ion helps reduce the osmotic pressure of water from 280 to 300 mOsm/kg to 200 mOsm/kg.