ROSIN SOAP Soap with Rosin—Common Yellow Soap.—Wbile making hard soap the addition of rosin increases its weight and bulk more than its value. Where rosin is used it is necessary to melt up the cake of soap with water after it has been removed from the lye, and boil. After boiling the mixture must be allowed to stand until cool, whcn the hard upper portion will be found to be pure yellow soap, and the soft lower portion containing the dregs can be scraped off and used another time. Rosin does not make true soap, but is useful in diluting animal fats, and when carefully prepared with strong alkalies and in not too large a proportion, it is of advantage be cause it is cheap and helps to make a good lather.
Rosin Soap. — A good method of making a rosin soap, where it is de sired to incorporate as much rosin as possible, is to saponify the rosin and the grease separately. By this means about 15 per cent of rosin can be used to advantage. Some cheap soaps contain as much as 25 or 30 per cent of rosin, but these are soft and apt to leave a resinous coating on the hands, with an offensive smell, and are in other respects unsatisfac tory.
One gallon of strong lye will sapon ify about 8 pounds of rosin. To ac complish this, first reduce the rosin to a powder, raise the lye to a boil, and introduce the rosin gently, stirring vigorously. Keep the mixture sim mering at the boiling point and stir constantly, otherwise the rosin will form in a cake at the top of the lye that will retard the operation. At best it will require about two hours. Meantime saponify the grease in an other kettle, and when both are done and still hot pour the rosin into the soap grease, boil, and stir vigorously until thoroughly incorporated. The addition of a small quantity of palm oil to the tallow will improve the soap by rendering it transparent and by giving it an agreeable flavor.
English Bar Soap.—Take 1 gallon of soft water, 1 pound of good stone lime, 31 pounds of sal soda, 1 ounce of borax, 2i pounds of tallow or other animal fat, 11 pounds of pulver ized rosin, and 1 ounce of beeswax.
First bring the water to a boil, then add gradually the lime and soda, stir ring vigorously. Next add the borax. Boil and stir until dissolved. Pour in the melted fat in a thin stream, stirring vigorously; add the rosin and beeswax; boil and stir until it thick ens and cools in molds. This old-time English method is a favorite family recipe throughout the United States.
Or dissolve 6 pounds of sal soda and 3 pounds of quicklime in 4 gal lons of soft water. Let the mixture settle and pour off the clear soda lye. Raise the lye to a boil and add grad ually 6 pounds of melted lard, mix ing gradually until it saponifies. This is a good soap for all domestic pur poses.
Soft Rosin Soap — Cold Process. Mix 2 ounces of powdered rosin with 2 pounds of lard. Add 3 pounds of potash. Mix and set aside 5 or 6 days. Place in a cask with 5 gal lons of boiling water and stir fre quently for about 2 weeks. This recipe will produce about 100 pounds of good soap.
Rosin Soap from Soda. — Dissolve 6 pounds of sal soda and 6 pounds of quicklime in 10 quarts of water. Boil from 20 minutes to a half hour. Re move from the fire and allow it to settle. Draw off the clear soda lye, bring it to a boil, and add 1 pound of powdered rosin and 7 pounds of melt ed fat. Boil until saponified, which will require a half hour or more.
Or use 2 pounds of sal soda and 8 ounces of stone lime with 2 quarts of soft water to make a lye. Mix to gether, boil, settle, and pour off the clear lye. Melt separately 1 pound of tallow, 14 ounces of rosin, and 2 ounces of palm oil. Bring the clear lye to a boil and add gradually the other ingredients. Mix, stir, and boil until saponified, which will require 20 to 30 minutes. This is a well known German recipe.