SOAP

is a composition resulting from the action of caustic alkali on animal or vegetable fats or oils, with or without the addition of rosin. For hard or washing soaps a mineral alkali (soda) is used with fats rich in stearine, whilst for soft soaps a vegetable alkali (potash) is used with fluid oils, or the oleic acids extracted' from solid fats. The addition of rosin to hard soaps is made to improve the lathering qualities, and when the proce is properly carried out is by far the best material for the purpose. Soap should be perfectly grease—an neutral, i.e. contain neither exce of alkali nor exce of the former means destruction to the fabric washed, and of the latter, lo of detergent powers. The fats in general use for making soap are For Hard soa^s For Soft Soaps And/or Low Qualities of Fish Oil, All fats are capable of being made into soap, even castor oil, but those given above are most in use, and their respective qualities are understood by their position in the list. Glycerine is a ** bye product" in the manufacture of soap. (See pa^e 673.) Among the most famous soap-makers are Me rs. Pears. Dr. Redwood, Ph.D., F.C.S., etc., said of SOCINUS, their soap " The proportion of alkalies to fats is absolutely: chemically correct. In a perfect soap neither preponderates. It is also free from any admixture of artificial colouring substances. The perfumes introduced are pure and perfectly harmle .” Stevens on M’Adam, Lecturer on Chemistry, Surgeons’ Hall, Edinburgh, said: " I can certify to its being a pure and genuine soap... practically devoid of causticity. It combines detergent with emollient properties, and may therefore be used with gTeat advantage for toilet and bath purposes, especially in the case of children and others whose skin is soft and delicate.’* The late Sir Erasmus Wilson, President of the Royal College of Surgeons, Charles Tichboume, LL.D., F.C.S., and others also have re-' commended