PEARL GRAY.
After scouring and rinsing well, prepare a warm bath (100-120° F.) with five per cent., of the weight of feathers, bisulphate of soda, to which add solution of Victoria blue and of extract of archil, according to sample. Acid violet may be used, but requires a temperature near the boiling point, which ought to be avoided wherever possible in dyeing ostrich feathers. To be on the safe side, make the solutions of the dyestuffs of medium concentration, use only the clear of them, or better filter the same, and add it slowly and gradually first in small doses, finally by drops, for which purpose the use of a burette with squeeze-cock is recommendable.