scouring: Fifty pounds of Greenbank pure caustic potash are put into
eight gallons of soft water; the potash dissolves immediately, heating
the water. This lye is allowed to cool, and then slowly added, with
continual mixing, to 20 gallons of cotton seed oil, mixed with 20 pounds
of melted tallow, the whole being brought to a temperature of about 90 deg.
F. After stirring for some minutes, so as to completely combine the lye
and oil, the mixture is left for two days in a warm place, when a slow
and gradual saponification of the mass takes place. If when examined the
oil and lye are then found not completely combined, the stiff soap is
again stirred and left two days, when the saponification will be found
complete, the result being the formation of about 330 pounds of very
stiff potash soap, each pound being equal to about two pounds of the
ordinary "fig" soap sold. The requisite quantity is thrown into the
scouring vat with about five per cent of its weight of refined pearl ash
to increase the alkali present, the weight depending somewhat upon the
kind of wool washed on purpose for which the soap is required. If the
wool is very dirty or greasy, rather a stronger soap is sometimes
advisable. This can easily be attained by reducing the quantity of oil
used to 18 gallons.

The advantages to be gained by the wool scourer or other consumer making
his own potash soap are that a pure, uniform article can always be thus
produced at a less cost than that at which the soap can be bought.
Potash soap, like soda soap now sold, is much adulterated, in addition
to all the impurities originally contained in the potash used, and
which, unlike soda soap, cannot be separated by any salting process.
Many other adulterations are added to increase the weight and cheapen
the cost. Silicate of potash, resin, and potato flour are all more or
less employed for this purpose, to the gain of the soap maker and at the
expense of the consumer.