The amount of water required in making a potash lye for soapmaking depends upon the process; in the cold process very strong lyes of about 70" Twaddell are used (that is, containing 35 per cent, potash); therefore about 21b. of water would he required for it; but for the boiling process weaker lyes of about 14° up to 35° T. (that is, containing 9 to 20 per cent, potash) are employed; for the latter, roughly 41b. to 91b. of water would be required. Caustic potash behaves like caustic soda in soapmaking when only a small quantity is added, the hulk of the alkali being soda; but if the potash is in excess, then the result will he a soft soap.