Volume 2

System of theoretical and practical chemistry ... / By Fredrick Accum.

  • Accum, Friedrich Christian, 1769-1838.
Date:
1807
Catalogue details

Licence: Public Domain Mark

Credit: System of theoretical and practical chemistry ... / By Fredrick Accum. Source: Wellcome Collection.

    381/546 (page 351)
    3. Gallic acid may likewise be obtained by exposing powdered nut-galls in a retort to a moderate heat. The acid by this means sublimes; part condenses in small white crystals, and part is obtained in a fluid form, from its combination with a portion of water contained in the galls. REMARK.—This process requires a great deal of pre- caution; the fire must be gradually raised, and slack- ened the moment coloured drops fall from the beak of the retort, otherwise the whole product becomes dissolved again, and is lost. Gallic acid, united to different bases, forms salts called ~ GALLATEs. ‘They have not hitherto been examined.