654 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



since the bisulphide, at 43 Fahr. and under, has little solvent 

 power, and at and above 68 Fahr. may produce a tension 

 that would seriously interfere with the operation. Finally, 

 the degree of freedom of the bisulphide from water is of 

 imjjortance, since moisture imparted to the seed hinders the 

 penetration of the bisulphide itself. 13 C, Dec, 1872, 1567. 



PEEVENTIXG EXPLOSIVENESS OF PETROLEUM. 



The great extent to which various mineral oils are used 

 for purposes of illumination or lubrication, and the conse- 

 quent increase of accidents from their emj^loyment, has made 

 it very desirable to devise some method by which they can 

 be made more or less innocuous, and Mr. Jordery suggests a 

 method which he maintains to be satisfactory, and applicable 

 in many cases. He claims to have ascertained that a small 

 quantity of soap-w^ort powder {Sapo7ia7'ia), when mixed with 

 petroleum, will produce an emulsion resembling thick glue, 

 which flows with great difficulty, and will not penetrate 

 through the cracks of badly joined vessels. Although it may 

 ignite on contact with flame, this is only the case with the 

 lighter and more volatile oils, and the flame is then feeble 

 and easily extinguished, and there is no tendency to explode. 



To secure this result, Mr. Jordery takes a given bulk of an 

 aqueous extract of soap-wort powder, and adds it, little by 

 little, to the petroleum oil, stirring it continually. The oper- 

 ation is entirely similar to that used in producing any kind 

 of emulsion, or in making mayonnaise for salad dressing, 

 which, as is well known, solidifies large quantities of olive-oil. 

 A quantity of oil equal to thirty times the volume of the ex- 

 tract of soap-wort employed can thus be used in the emul- 

 sion. The product obtained is consistent and stable, and is 

 not disturbed bj'' the ordinary motion to which oil is subject- 

 ed in transportation or in warehouses, and is said not to be 

 altered in the least by the amount of water combined with 

 it. In the case of the crude oils, the powder itself, without 

 the aqueous extract, is sufficient to produce the desired emul- 

 sion. Nothing is easier, according to Mr. Jordery, than to re- 

 store the oil, thus prepared, to all its limpidity and its prim- 

 itive qualities. For this purpose it is only necessary to al- 

 low a few drops of carbolic acid to fall upon the surface, or 

 a still larger amount of crystallizable acetic acid. The sep- 



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