The bile obtained from the gall bladder of a bovine animal. Ox-gall is used as the expanding and binding medium for the colors used in marbling of paper and other materials.
In its original state it is yellowish or greenish brown, but becomes clearer and dark brown when allowed to settle. The liquid is then drawn off and mixed with alcohol. Its effect on the colors is to make them spread out in large flat rings when they are dropped on the water bath. Ox-gall is also used in engraving and lithography.