Take 50 gallons of boiling water;
150 pounds of sulphate of iron; dissolve along with
10 pounds of alum; which partly saturate by the gradual
addition of
5 pounds of crystals of soda; and in this mixture dissolve
50 pounds of pyrolignous acetate of lead. Allow the whole to
settle, and draw off the clear supernatant liquid.
For furniture prints this bath should have the spec. grav. 1·07.
The calico being padded in it, is to be dried in the hot-flue; and after
48 hours suspension is to be washed in water at 170° containing some
chalk, by the wince apparatus. It is then washed, by the same apparatus,
in hot water, containing a pailful of soda lye of spec. grav. 1·04.
For light tints the padding liquor should be reduced to the spec. grav.
1·01. The dye in either case may be brightened by wincing through a weak
solution of chloride of lime.
Nitrate of iron diffused through a body of water may be also used for
padding, with alternate washings in water, and a final wincing in a weak
alkaline lye.
With a stronger solution, similar to the first, the boot-top colour is
given.