Tallow Soap: 1 can of lye, 6 lb beef tallow, 2 3/4 pints water; Lye solution 90øF, fat 130øF. Substitution of 1 lb of tallow with lard, coconut or olive oil will improve the lathering properties.
Coconut Oil Soap: 1 can of lye, 4 1/2 lb coconut oil, 2 1/2 pints water; lye solution 70øF, oil 110øF. This soap gives a very profuse but thin lather. Substitute tallow or lard for part of this oil for thicker lather.
Glycerine Soap: Add 6 ounces of glycerine to any soap shortly after the lye solution has been added.
Imitation Castile Soap: A very high grade soap which in many respects is superior to castile soap can be made as follows: 24 oz olive oil, 38 oz tallow, 24 oz coconut oil, 1 can lye, 2 pints water; fats 90øF, lye solution 90øF.
Abrasive Soap Paste: A fine soap for household scouring and for mechanic's hands. Shave 3 lb homemade soap and melt in 3 pints water. Add 3 oz light mineral oil. When this is thoroughly blended, allow it to cool to a thick consistency and work in 5 lbs of pumice stone. Keep tightly covered.
Abrasive Soap: Follow recipe for making soap. When mixture thickens add, gradually 5 lb of pumice stone and stir until the mixture is thoroughly blended or all the lye is incorporated. Pour into mold and cover.
Jelly Soap: For use in washing machines and for washing dishes. Lye hard soap converted into jelly soap is convenient and economical to use. Cut 1 lb of hard soap into fine shavings and add 1 gallon water. Boil for about 10 minutes then transfer to a suitable vessel to cool. Keep covered to prevent drying out. Jelly soap melts in hot water immediately and makes thick suds.
Liquid Soap: 4 lbs cottonseed oil, 1 1/4 lbs coconut oil, 3 pints glycerine, 6 1/2 pints alcohol, 7 pints water. Dissolve 1 can of lye in a mixture of 3 1/2 pints each alcohol and water and heat to 125øF. Have the oils at 150øF and add a few ounces of the lye solution, stirring slowly and evenly. When saponification is about complete, add a few ounces of the lye solution with continued stirring and repeat until all the lye solution is in. Cottonseed oil is sometimes rather hard to saponify, and slight separation of oil might occur after the above procedure if the lye has been added too rapidly. In this case, allow it to stand 24 to 48 hours with occasional stirring. When a perfect mixture is obtained with no separation of il, add the glycerine and the remaining alcohol and water. Allow to stand for a couple of days and if any sediment settles out, filter or syphon off the clear liquid. Then color and perfume as desired.
Rosin Soap: Rosin added to soap increases its lathering properties but makes a darker and softer soap. It is frequently used as laundry soap. Add 8 oz crushed rosing to 5 1/2 lb clean fat and raise the temperature until the rosin is melted or dissolved in the fat. Cool the mixture to 100øF and add the lye solution made by dissolving 1 can of lye in 2 1/2 pints of water and cooling to 90øF. If soap containing more rosin is desired, for every 8 oz of rosin added, decrease the amount of fat used by 8 oz. The total weight of rosin and fat should be 6 lb for each can of lye.
Hard soap by the boiling process: Prepare in usual manner but do not pour into molds. Keep covered and set in a warm place overnight. The next day, cut into fine shavings, add 7 pints of water and melt with gently heat and occasional stirring. When all lumps are dissolved, raise the heat and continue boiling until of a syrupy nature when dropped off of the spoon. Then pour into molds. Boiling process soaps require more aging than cold process soaps. Perfumes, colors and other special materials are added after the soap has cooled somewhat, but while it is still fluid enough for pouring.
Source: "Grandma's Olde Fashioned Soap Making"