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Soft toilet soaps or
creams may be prepared from fresh lard with a small addition of cocoanut oil
and caustic potash solution, by the cold process or by boiling. For the cold
process, 23 parts of fresh lard and 2 parts of Cochin cocoanut oil are
warmed in a jacketed pan, and when the temperature reaches 133° F., are
treated with 9 parts of caustic potash and 2½ parts of caustic soda
solution, both of 38° be. Strength, the whole being stirred until
saponfication is complete. The soap is transferred to a large marble mortar
and pounded along with the following scenting ingredients: 0.15 parts of oil
of bitter almonds and 0.02 parts of oil of geranium rose, or 0.1 parts of
the latter, and 0.05 parts of lemon oil. The warm process is preferable,
experience having shown that boiling is essential to the proper
saponfication of the fats. In this method, 80 parts of tard and 20 parts of
Cochin cocoanut oil are melted together in a large pan, 100 parts of potash
lye (20° Be) being then crutched in by degrees, and the mass raised to
boiling point. The combined influence of the heat and crutching vaporizes
part of the water in the lye, and the soap thickens. When the soap has
combined, the fire is made up, and another 80 parts of the same potash lye
are crutched in gradually. The soap getst thicker and thicker as the water
is expelled and finally throws up roses on the surface, indicating that it
is nearly finished.
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