wood-tar

As aniline is a product of coal-tar, so picamar is a product of wood-tar; and as the former gives a purple with hypochlorites, so the latter yields a blue with baryta-water.

Field's Chromatography or Treatise on Colours and Pigments as Used by Artists George Field

The colours obtained from coal-tar have become household words, and it is not impossible that those from wood-tar may be some day equally familiar.

Field's Chromatography or Treatise on Colours and Pigments as Used by Artists George Field

Picamar blue is produced when a few drops of baryta-water are added to an alcoholic solution of impure picamar, or even to wood-tar oil deprived of its acid.

Field's Chromatography or Treatise on Colours and Pigments as Used by Artists George Field

At present wood-tar is comparatively unexplored, but the fact that picamar furnishes a blue is at least as suggestive and hopeful as that transient purple colouration by which aniline was once chiefly distinguished.

Field's Chromatography or Treatise on Colours and Pigments as Used by Artists George Field

Our object in noticing this blue has been two-fold: first, to direct attention to wood-tar as a possible source of colour; and secondly, to point to pittacal as a possible substitute for indigo, possessing greater durability.

Field's Chromatography or Treatise on Colours and Pigments as Used by Artists George Field