PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION 651 



found in gas manufactories, may also be abstracted in small quantities 

 from coal oil waste, but it is not an economical source. 



With regard to crude rock oil or petroleum, it may now be said that its 

 products have useful applications. The lighter compounds, varying from 

 58 to 63 (Baume's scale), are known as naptha, and form a perfect substi- 

 tute for turpentine. It is used as high as 65 in making the illuminating 

 substance known as " burning fluid." The still lighter product, ranging 

 from 65 to 75Baume, is called benzine, and is a substitute for camphene; it is 

 also used for cleaning wool and woolen cloth, and for dissolving india-rubber. 

 The product of petroleum ranging from 58 to 43, is used as an illuminating 

 oil. The crude product below 43 and above 30 is known as paralfine oil, 

 and used for lubrication, also, when mixed with linseed oil, for painting. 

 It is also found to be very valuable to the currier in finishing leather. Below 

 30 the product is designated a residuum, and is used for making gas. The 

 St. Nicholas Hotel, in the city of New York, is lighted by it, which effects 

 a saving of about $10,000 per annum, as compared with the cost of light- 

 ing that establishment with ordinary coal gas. 



In refining crude petroleum, a large quantity of sulphuric acid is used. 

 After it had been employed in the treatment of petroleum, it was formerly 

 looked upon as refuse, but now it is readily sold to the manufacturers of 

 superphosphate of lime, to be used in the dissolving of bones. 



Dr. J. B. Rich remarked, that, in examining the different instruments and 

 methods for testing the explosibility of the oils described by the last 

 speaker, a report of which was presented last year to this association, he 

 found that vapor would pass off from them at all temperatures down to 40^ 

 Fah., and that the amount of vapor depended on the quantity of the oil 

 Tinder test. 



Mr. B. Gai'vey said, in his experiments with oils, he found that if they 

 were exposed to the air for some time, the lighter particles of the oil would 

 evaporate, and a lubricating oil be left. 



Mr. Overton alluded to a fatal accident resulting from the use of petro. 

 leum. 



Mr. Page replied that the material so used must have been a mixture of 

 light and heavy products. There would be no accidents, if frauds were 

 not practiced by dealers. Such mixtures are not made by petroleum man- 

 ufacturers, because the article would be unsaleable. All oils are now tested 

 by regularly appointed inspectors. The oils therefore coming from the 

 manufacturer may bo regarded as perfectly safe. The vapor spoken of 

 as passing from illuminating oil at all temperatures, rises very slowly, and 

 is heavier than naptha vapor. It does not occulate in such a quantity as 

 to form, eveu in a long time, an explosive compound. No fires or accidents 

 have ever occurred in using these tested oils for illuminating purposes. 



The subject selected for the next discussion is, the use of water or its 

 vapor as fuel. 



Adjourned 



