i,( i( )(;-AS. 



341 



the fact that the output of tlie Stassfurt mines is no longer 

 available on account of tlie naval blockade. The present market 

 value of " loog: as " as a source of potash for agricultural pur- 

 ]Joses is_ doubtless, therefore, more than twice the normal value 

 of kainit. The attention of manure merchants is directed to 

 " loog as," in the hope that they will be able to make up in some 

 measure for the temporary loss to the world of the output of 

 the Stassfurt mines. 



In Middelburg alone it is estimated that, without any fur- 

 ther burning operations, there are at least too tons of the ash . 

 available for immediate use. It must be borne in mind that 

 the " carbonate form has considerable drawbacks from the 

 manurial point of view. Its use in the drier localities is not 

 to be recommended, except on soils which contain soluble 

 calcium salts, ])ut there would seem to be no reasonable objec- 

 tion to its general use in the more moist districts. 



It Avould prove an excellent source of potash in the case 

 of soils which have a tendency to acidity, and is therefore likely 

 to prove valuable for the grain-growing areas in the Western 

 Province. 



With regard to its use as a soap-making agent, its local 

 value ai^pears to vary between 3s. 6d. to 5s. per 150 lbs. 



The following recipe is given for its use as a soap-making 

 agent : — 



To two iiuckets of asli add four to five of water. Then either hoil for 

 an hour or two or allow to stand, with occasional stirring-, for 48 hours. 

 Whichever method is adopted, the resulting solution is allowed to clarify, 

 after wliich it is drawn off. 



The solution is tasted liv wetting tlie finger and applying it to the 

 tip of the tongue. Tf a burning sensation is experienced, the solution is 

 of sufficient strengtli : if not, a larger quantity of ash must be employed. 



A Inicketful of tlie extract is then placed in a kafiRr iron cooking pot 

 together with 30 lbs. of fat. The whole is brought to the lioil and main- 

 tained at that temperature for several hours during each of the ne.xt eiglit 

 or ten days. The mixture is repeatedly stirred, and fresh additimis of 

 the w-ater extract are made from time to time, so as to approximately 

 maintain the original Inilk of the contents. 



The end has been reached when on taking out the stirring spoon, 

 it is found that the watery fluid runs away from tlie soap. 



Two or three pints of salt are now added, and the boiling continued 

 until a " honey-looking " appearance is noticed. The salt effects the 

 complete separation of the soap from the liquid, with the result that the 

 former, on cooling, forms a crust with the liquid below it. 



The next operation consists in cutting the soap crust up into bars. 



In practice it is not always possible to hit off the exact quantities of 

 fat and of extract to take. .An excess of the former is indicated by the 

 cracking of the resulting soap, a deficiency by its "biting" properties. In 

 the former case the mass is again boiled up with the addition of more 

 extract, while in the latter case it is boiled up again after the addition of 

 salt water. 



The Chemistry of the process is something like the follow- 



ing 



I. The treatment of the ash with water dissolves out the potassium 

 with sodium carbonates. 



