202 ILLINOIS ACADEMY OF SCIENCE 



which until ten years ago was allowed to waste, consists of 

 the lighter oils in natural gas. It is extracted by subjecting 

 the gas to great pressure and then allowing it to expand and 

 cool. The gasoline condenses at the same time. The rich- 

 ness of the gas varies from about two to six gallons of gaso- 

 line per 1,000 cubic feet of gas. 



In 1911, 7,425,000 gallons of casing-head gasoline was 

 manufactured in the United States, whereas in 1914 42,652,- 

 000 gallons of this material found its way to market. It is 

 estimated that with the same per cent of increase the year 1915 

 showed about 75,000,000 gallons of casing-head gasoline 

 which was an absolute loss until a few years ago. However 

 important this source of gasoline is, there remains a demand 

 for about 975,000,000 gallons which must be supplied from 

 crude oil. 



In 1915 about 108,000,000 barrels of high-grade crude oil 

 was produced. In order, then, to furnish the supply of 

 gasoline, it is necessary that a barrel of high-grade crude oil 

 under older refining methods must produce about eight gal- 

 lons, nearly 25 per cent of gasoline. With most crude oils 

 this per cent was about the maximum, but recently new meth- 

 ods of refining have been introduced ; namely, the Rittman, 

 Burton, Washburn, Seeger, etc., all of which depend on the 

 theory that crude petroleum consists of a mixture of mole- 

 cules in which the smaller ones are gasoline, naptha, etc. ; the 

 larger ones kerosene; still larger ones, the lubricating oil, and 

 so on down to the heavy residue. The new processes de- 

 pend on breaking up the larger molecules into smaller ones by 

 heat and pressure, either in gaseous form or as a liquid. It 

 has been found that the heavier residue which is left from 

 present methods of refining may be divided by extreme heat 

 and pressure into gasoline and heavier liquids. 



There is at the present time and probably will continue to 

 be an excessive demand for gasoline in excess of the kerosene 

 and lubricating oils. The new processes will probably enable 

 the refiners to produce a very large per cent of the gasolines 

 for which there is an excessive demand, and to leave only 

 small amounts of the heavier products which are now a drug 

 on the market. These processes, together with the rapid in- 



