EDITORIAL. 233 



sponded in the method of manipulation showed that alcohol was more 

 efficient than gasoline and they also proved that equal volumes of gasoline 

 and alcohol produced about the same power. This result is not usually 

 achieved in practice. Ordinary commercial gasoline engines of station- 

 ary or marine type will consume from 1.5 to 2 times as much alcohol 

 as gasoline when operated under the same conditions. 



Alcohol is especially suited to air-cooled automobile engines, as the 

 exhaust is not so hot as when gasoline or kerosene is used, while on the 

 other hand the temperature of the cylinder may be hotter without 

 danger of backfiring. The storage and use of alcohol in engines is 

 much less dangerous than that of gasoline or petrol and the engines 

 operating on the former run more quietly and produce a less offensive 

 odor. No more skill is required to operate an alcohol engine than 

 one arranged for gasoline or kerosene. 



The relative heat values of gasoline, alcohol and coal are shown by 

 the following approximate numbers: 



Calories. 

 Gasoline 11,100 



Alcohol (100 per cent) 7,183 



Pennsj'lvania anthracite 7,.500 



The calorific value of alcohol is of course lower by impurities, so 

 that commercial (90 per cent) alcohol has a calorific value of about 

 60 per cent of that of gasoline, or a comparative heat value of over 

 70 per cent by volume. Alcohol of 85 per cent is the common grade 

 of industrial alcohol used in Europe. The United States Geological 

 Survey found diflSculties in starting and regTilating when the experi- 

 menters employed 80 per cent alcohol and the fuel consumption increased 

 more rapidly than the percentage of alcohol decreased. 



The effect upon motors, lamps, etc., of using denatured alcohol has 

 been discussed and deterioration has usually been attributed to tlie 

 denaturant.'' It may be possible that all of the evils coming from the 

 latter may be remedied in the future. Lucke and Woodward found 

 that the interior of an alcohol ejiginc had no tendency to become sooty, 

 as is the case with gasoline and kerosane and there was no undue corro- 

 sion of the interior due to the use of alcohol. 



The raw materials from which industrial alcohol comes consist of 

 those substances which contain starch, sugar and other fermentable 

 bodies, named in the order of their importance, capable of easily being 

 converted into a fermentable sugar. The cereals, rice, wheat, oats, rye, 

 maize and barley, the potato, cassava or manioc and some other roots 

 contain large percentages of starch. From all of these as well as from 

 sugar cane and sugar-cane molasses, sorghum and fruit juices which 

 contain large percentages of sugars, alcohol is made. The artichoke 



^Suchemin, R. : Rev. gin. chim. (1906), 9, 437 to 443; Lucke, C. E. and 

 Woodward, S. M. : loc. cit. 



