ammonia
being liberated; the use of sodium and potassium bibasic phosphate (Eng.
Pat. 25,357, 1899); a substance formed by treating albumen with formalin
(Eng. Pat., 8,582, 1900); wheat glutenin "albuminoses" (albumen after
acid or alkaline treatment); malt extract; and egg, milk, or vegetable
albumen.

The colouring matter used may be of either vegetable or coal-tar origin,
and is dissolved in the most suitable medium (lye, water, or fat). The
older types of colouring matter--such as cadmium yellow, ochres,
vermilion, umbers--have been superseded.

In the production of washer household soaps, a small quantity of perfume
is sometimes added.

_Disinfectant Soaps._--To the soap base, which must be strong to taste,
is added from 3 to 4 per cent. of coal-tar derivatives, such as carbolic
acid, cresylic acid, creosote, naphthalene, or compounds containing
carbolic acid and its homologues. The incorporation is made in the
crutching pan, and further crutching may be given by hand in the frames.

_Framing._--The object of framing is to allow the soap to solidify into
blocks. The frames intended for mottled soaps, which require slow
cooling, are constructed of wood, often with a well in the base to allow
excess of lye to accumulate--for other soaps, iron frames are in general
use. The frame manufactured by H. D. Morgan of Liverpool is shown in
Fig. 9.

As soon as the frame is filled, or as soon as the crutching in the frame
is finished, the soap is smoothed by means of a trowel, leaving in the
centre a heap which slopes towards the sides. Next day the top of the
soap is straightened or flattened with a wooden mallet, this treatment
assisting in the consolidation.

[Illustration: FIG. 9.--Soap frame.]

[Illustration: FIG. 10.--Slabbing machine.]

The length of time the soap should remain in frames is dependent on the
quality, quantity, and season or temperature, and varies usually from
three to seven days. When the requisite period has elapsed, the sides
and ends of the frames are removed, and there remains a solid block of
soap weighing from 10 to 15 cwt. according to the size of frame used.
The blocks, after scraping and trimming, are ready for cutting into
slabs.

_Slabbing._--This may be done mechanically by pushing the block of soap
through a framework containing pianoforte wires fixed at equi-distances
(Fig. 10, which shows a machine designed by E. Forshaw & Son, Ltd.), or
the soap may be out by hand by pulling