Today we get it out of a can but this was not the case not that long ago, especially during the 19th Century. Below is some basic information and recipes for making the shaving cream of the past.
Soft Toilet Soaps Of Potash.
White Soft Soap.
Soaps of potash are among the most valuable cosmetics prepared by the soap-maker or perfumer, and much care should be exercised in having the purest materials, the greatest cleanliness, and the true equivalents of the parts, as any carelessness in them particularly deteriorates the quality of the product.
To prepare this soap very white, operate in the following manner:—
Melt in a sheet-iron kettle of a capacity of about 50 gallons, 50 pounds of white fat, and 13 lbs. of cocoa oil. When the fatty matters are entirely melted, add 50 lbs. of lye of potash at 20° or 21° B. Stir all the time, so as to aid the saponification, the temperature being kept at from 60 to 65.5° C. (140° to 150° F.). Under the influence of heat and stirring, the aqueous part of the lye evaporates and the mixture acquires a thicker consistency. Sometimes it happens that a part of the fatty matters separates; this effect is produced especially when the temperature of the mixture is raised near the boiling point, because at that temperature, concentrated lyes have little affinity for fatty substances. This effect may also be produced by the insufficiency of alkali in the mixture. In the first case the homogeneity is re-established by moderating the action of the heat, and in the other, by pouring into the kettle a portion of strong lye necessary to complete the saponification.
This first stage of the operation lasts about four hours. To obtain a perfect soap, add a new portion of 10 lbs. of lye of potash at 16° B., and be careful to keep the mixture very uniform by a continual stirring. Keep the temperature below the boiling point, and as much as possible between 60° and 65.5° C. (140° and 150° F.).
The saponification is finished when the paste has acquired a very thick consistency; at this point turn off the heat.
Many perfumers prepare this soap in iron kettles with a double bottom, heated by steam; some use silver kettles which are preferable, because the soap will retaiu in them all its whiteness.
Almond Shaving Cream.
Take a few pounds of the above soft soap, introduce it into a marble mortar, and strongly triturate with a wooden pestle. The operation is finished when the soap forms a soft and homogeneous paste; the more it is beaten, the finer it will be. To perfume it, incorporate from \\ to 2 drachms of oil of bitter almonds per pound.
Thus prepared, this soap forms an unctuous paste very soluble in water. When it contains some cocoa-nut oil, it is yet softer.
Rose Shaving Cream.
To give this soap a slight rose color, when pearling add one-quarter to one-half a drachm of vermilion per pound of soap, perfume with otto of rose; it then takes the name of rose shaving cream.
Ambrosial Shaving Cream, Crime d'Ambrosie. — Perfume with liquid storax and benzoin, oils of bergamot and cloves, and color purple with tincture of archil.
Shaving Cream By Boiling.
In some instances, a soap by boiling will prove more satisfactory, particularly when it is mixed and milled with a soda soap to form shaving tablets. The cream is rarely of so white a color as that made by the cold process. To proceed, take 30 pounds of white grease to 45 pounds of potash-lye of 17° B., and boil gently while stirring, until a paste is formed, when boil more briskly until the vapors nearly cease, and the soap forms into an almost perfect jelly when it is finished, and when cold it should be almost neutral.
Source: A Technical Treatise on Soap and Candles ©1881