DANGEROUS KEROSENE AND ITS DETECTION. 461 



DANGEEOUS KEROSENE AND THE METHODS FOE 



ITS DETECTION. 



By Dr. JOHN T. STODDAED, 



PROFESSOR OF CHEMISTRY IN SMITH COLLEGE. 



KEROSENE, in virtue of its cheapness and the brilliant light it 

 gives, has found its way into almost every house. And yet fre- 

 quent and often horrible accidents prove that much of the oil now 

 sold is of a most dangerous character. It is the recognized duty of 

 the State to render the sale of such oil impossible by proper inspec- 

 tion. Almost daily reports of loss of property and life, as the result 

 of the use of unsafe kerosene, show, however, that this official control 

 fails to effect its object. This may be due, in a measure, to the un- 

 doubted negligence of cities and towns to appoint competent inspect- 

 ors if, indeed, any appointment is made or to the carelessness of 

 the inspectors ; but of greater importance even than this are the low 

 standards adopted, and the unreliability of the tests which are used to 

 determine the character of the oil. 



It is the object of this paper to consider the conditions of safety 

 in an oil used for illuminating and heating purposes, and to give a 

 brief sketch of the principal methods which have been proposed for 

 determining this important point. 



Petroleum, from which kerosene is prepared, is, as is generally 

 known, a mixture of a large number of intimately related compounds of 

 widely differing volatility. Some are gaseous, and escape in this form 

 as the petroleum issues from the ground, while others form the solid 

 paraffine. The middle portions of the crude oil are separated from the 

 more and less volatile compounds by distillation, and after a further 

 process of purification go into the market as kerosene. The entire 

 removal of the lighter and more volatile portions, which are known as 

 naphtha and benzine, is of the utmost importance, for it is in their pres- 

 ence that the danger lies. Alone, they are easily ignited, and alone 

 or mixed even in small proportion with kerosene, they readily emit 

 vapors which are inflammable and which with air form an explosive 

 mixture. 



An oil is safe only when it will not yield these dangerous vapors 

 at any temperature which it is liable to assume. This temperature 

 depends obviously (1) upon that of the place where the oil is kept 

 or used, and (2) upon the influence of the heat of the burning wick in 

 warming the oil in the reservoir of the lamp. As the result of care- 

 fully conducted experiments with lamps of different patterns, it has 

 been found* that the maximum increase of temperature of the oil 



* " Zeitschrift fur anal. Chem.," xxi, 332. 



