CHEMICAL SCIENCE. 231 



300 and 400 Fahr. the mixture of the two bodies is complete. If the tem- 

 perature be maintained for some time, and the mixture be then several times 

 washed with warm water, or better, with water acidulated with hydrochloric 

 acid, we obtain a fat which, when submitted to distillation, gives the fat 

 acids which correspond to it, and with an insignificant production of acro- 

 leine. The wash-waters carry off almost the whole of the chloride employed, 

 so that by evaporation this may be again used for another process. The fat 

 acids are thus produced in as great quantities as by the common methods, 

 and have the same appearance, the same qualities, and the same fusing 

 point as those which are obtained after saponification by sulphuric acid. To 

 operate well and quickly, the mixture should be heated rapidly, until by the 

 reaction of the two bodies on each other, which is of considerable violence, 

 the vapor of water is abundantly evolved. 



In fact, the washing with acidulated water may be dispensed with; but 

 the products then obtained by distillation are softer. If, however, the distil- 

 lation be carried on by means of a current of superheated steam, this defect 

 may be in a great measure cured. In all our experiments, the use of super- 

 heated steam produced the products more rapidly, more firm, and less 

 colored. 



The experiments were instituted with a view to allow the inhabitants of 

 South America to convert their fats into stearic acid, without the danger and 

 expense of transporting sulphuric acid to those countries. In an economical 

 point of view this problem is resolved, since the chloride of zinc is sold at 

 Marseilles never higher than two and one-fourth cents per pound, and, 

 packed in cases or barrels, can be shipped without danger or inconvenience. 

 Comptes Rendus de I' Academic des Sciences, Paris. 



CONDENSED LYE, OR PORTABLE ALKALI. 



The hydrated oxides, soda and potassa, are known in commerce as the 

 caustic, mineral, and vegetable alkalies. Being very deliquescent, it has not 

 been found practicable, until quite recently, to put them up for sale in small 

 parcels, so as to render them easily accessible to families, for soap-making 

 and other useful purposes. 



Various devices have been tried, at different times, to secure the caustic 

 soda in air-tight packages. A patent was obtained October 18-30; one mode 

 for doing which was to wrap up the small blocks in paper impregnated with 

 a resinous composition ; but this was soon discovered to be inefficient, and 

 abandoned, because the caustic soda, possessing a powerful affinity for all 

 substances containing the elements of water, namely, hydrogen and oxy- 

 gen, quickly corroded the resinous paper, and destroyed the wrapper and 

 envelope. 



The only mode which had heretofore proved measurably successful in se- 

 curing the caustic soda from atmospheric air and moisture, was the putting 

 it into metallic boxes; to this mode there are many serious objections, on 

 account of the difficulty of getting it out of the boxes, being apt to burn the 

 fingers and clothing, wherever it comes in contact with them. 



Very recently, Dr. Chase, of Philadelphia, has succeeded, after various 

 experiments, in rendering paper wrappers proof against the corrosive action 

 of caustic alkali, by means of Paraffine. This being a hydro-carbon, is in- 

 susceptible to the corrosive action of the caustic soda, and is found in prac- 

 tice to be perfectly efficient. 



