• WordNet 3.6
    • n pyrogallol a toxic white lustrous crystalline phenol used to treat certain skin diseases and as a photographic developer
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Webster's Revised Unabridged Dictionary
    • n Pyrogallol (Chem) A phenol metameric with phloroglucin, obtained by the distillation of gallic acid as a poisonous white crystalline substance having acid properties, and hence called also pyrogallic acid. It is a strong reducer, and is used as a developer in photography and in the production of certain dyes.
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Century Dictionary and Cyclopedia
    • n pyrogallol A white crystalline compound, C6H3(OH)3, obtained by the distillation of gallic acid, whence the name: also made synthetically. It is used as a photographic developer. The alkaline solution is sometimes used in gas analysis to absorb oxygen. It has a bitter taste, is poisonous, and melts at 132.5–133.5° C. Also called pyrogallic acid.
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Webster's Revised Unabridged Dictionary
Pyrogallic, + -ol,


In literature:

Newton employs it in combination with pyrogallol and soda in the development of bromo-gelatine plates.
"Scientific American Supplement, No. 483, April 4, 1885" by Various
Councler substitutes phloroglucinol for pyrogallol, with the advantage of doing away with the digestion at high temperature.
"Researches on Cellulose" by C. F. Cross
The light from ozone acting on pyrogallol solution is especially bright under certain conditions.
"The Nature of Animal Light" by E. Newton Harvey
The pyrogallol tans yield very different amounts of bloom.
"Animal Proteins" by Hugh Garner Bennett