118 



POWER AND THE PLOW 



vaporize and burn kerosene than to handle gasoline, also the 

 practice of running kerosene engines on gasoline for a moment 

 on starting. 



The only commercial standard of quality for liquid fuels 

 ordinarily considered, aside from their color, is the Baum6 



Asphalt 



Residuum 

 and Wast* 



T>ennsylvaniaOih California Oils 



Composition of crude oils 



gravity, in which the weight is compared with that of water. 

 Water, which weighs eight and one third pounds per gallon 

 at 60 F., is placed at 10 on the Baume scale. Liquids heavier 

 than water have a lower value and lighter liquids a higher value. 

 The Baume gravity may be calculated by the following formula 



