Marseilles soap

Three pounds of olive oil gave a block of soap weighing six pounds ten ounces, which, an exposure to the air for two months, became four pounds fifteen ounces. It was then dry and perfectly solid, of excellent color, resembling that of Marseilles soap. By further exposure in a dry place it became still lighter, owing to loss of water. 

Marseilles Soap.—This variety of soap is produced by the saponification of olive oil alone. The process does not materially differ from that described for white soap. Tho duration of the operation is longer or shorter according to the quality of the oil. Some manufacturers use, in the fabrication of this soap, a certain proportion of poppy oil with the olive oil and the addition is rather beneficial than otherwise, as the soap produced is less hard, and consequently more easily applicable to detergent purposes. It is at present manufactured on a considerable scale in this country. 

An alcoholic soap solution (white Marseilles soap in about 60% alcohol, see Water, Vol. I) is prepared of such concentration that 1 c.c. corresponds with 0-0005 gram of CaO. The titre is controlled by means of barium chloride solution containing 0-436 gram of crystallised barium chloride per litre 40 c.c. of this solution should require 8 c.c. of the soap solution to form a persistent froth after agitation. 

Fastness against milling, (a) Neutral milling The sample is made into a skein with an equal quantity of white wool or cotton and treated at 300 C. in a bath (40 times the weight of the sample) containing 20 grams of Marseilles soap per litre of distilled water it is scoured with the hands in the liquid, left in the bath for 2 horns, washed and dried. 

Alkaline milling The treatment is as in (a) but at 400 C. and in a bath containing 20 grams of Marseilles soap and 5 grams of Solvay soda per litre of distilled water. 

Fastness against soap. The dyed silk is made into a skein with white linen or cotton, then immersed for 10 minutes in a soap bath (10-15 grains of white Marseilles soap per litre) heated to 40-45° C., washed in running water and dried. 

The preparation of B. mori fibroin solution is summarized as follows. The cocoon was degummed twice with 0.5% Marseilles soap solution at 100°C for 0.5 h and then washed with distilled water. The degummed B. mori silk fibroin was dissolved in 9 m MLiBr at 40°C. After dialysis against distilled water for 4 days, the solution was clarified by spinning in a centrifuge at lOOOOrpm for... 

It has been ascertained that three pounds of olive-oil will yield five pounds of marbled Marseilles soap, whereas the same amount of oil will only produce four pounds four ounces of white soap, which proves that the former retains more water in its composition than the latter. French Marbled Soap.—Dussauce, in his admirable Treatise on the Manufacture of Soap, " gives an elaborate description of the manufacture of marbled soaps, as con-duoted in France, from which we give the following extracts —... 

The ordinary commercial Marseilles soap contains from 62 to 65 per cent, of fatty acids. 

Another experiment was made by mixing Marseilles soap with its weight of water and one quarter of its weight of olive-oil. The temperature and operation were the same. The matter, after the reaction, had all the properties of an acid soap it was soluble in cold alcohol and in an aqueous solution of potassa or soda. Acids separated from it a fatty substance likewise entirely soluble in cold alcohol and alkaline solutions. 

The discovery of bases is also very ancient. In prehistorical times, plants were utilized because they could be made into soaps. They had to be burned, and the cinders could be made into soaps, such as Marseille soaps or Aleppo soap, depending on where they were made. The plant s alkaline properties, whether the species were Salicomia or simply common soda (Salsola soda [1]) (Fig. 1.2), define the properties that allow soaps to be made. 

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