1 882. 137 Trans. N. V. Ac. Set. 



rency of the crystals, and their perfection of form, render them quite 

 remarkable. 



Mr. Arthur H. Elliott then read the following paper, which 

 was largely illustrated with specimens of the various forms of ap- 

 paratus described, and by experiments : 



THE METHODS OF ASCERTAINING THE SAFETY OF KEROSENE OIL. 



Before speaking of the various methods that have been proposed, and 

 are now in use, for ascertaining the safety of kerosene oil, it will per- 

 haps be well to look over the conditions of the problem. As we all 

 know, kerosene oil is the product of the distillation of crude petroleum. 

 This crude petroleum is made up of a number of oily liquids having 

 different boiling points — in other words, liquids that give off vapors at 

 different temperatures. These temperatures vary from 65° to 400° or 

 500° F. From 100 parts of crude petroleum there is obtained by dis- 

 tillation, in round numbers : 



Benzine, Naphtiia, etc 1 5-16 parts. 



Kerosene Oil 55 parts. 



Paraffine, Lubricating Oils, etc., 30 " 



It will thus be seen that only about half the crude petroleum is fit 

 for burning. For the benzine, naphtha, etc., are too volatile and dan- 

 gerous, while the paraffine is only fit for lubricating, being too thick to 

 flow through an ordinary lamp-wick. On account of these two facts, 

 the kerosene oil is the most valuable product of the distillation of crude 

 petroleum, and brings the best price in the market. Benzine is worth 

 only half as much as kerosene oil, while naphtha and paraffine bring only 

 one-third as much. 



From these circumstances it follows that in distilling crude petro- 

 leum, the oil-rehner tries to get as much kerosene oil in his product as 

 possible. To increase the quantity of kerosene oil given by the petro- 

 leum under treatment, the refiner may do one or both of two things. 

 He may collect as kerosene those products which boil at either a lower 

 or a higher temperature than good kerosene. The latter action is not 

 so important as the former. In the last case an oil is obtained that is 

 too thick and heavy to burn in ordinary lamps, and does not give a 

 brilliant light. But in collecting the naphthas, which boil at a lower 

 temperature than good kerosene, several very important results are pro- 

 duced. Besides adding to the quantity of kerosene in the products, 

 these low boiling oils increase very much the brilliancy of the light 

 given by the kerosene. Here let me state exactly what I mean by this 

 expression. I do not mean to say that the amount of light obtainable 

 irom a given quantity of low-boiling oil is greater than that obtained 



