92 



Our Surroundings 



water returns to liquid form when it strikes a cold surface. The 

 whole process is called distillation. 



Kerosene was used extensively, and is still used to some 



extent, for lighting, heating 

 and cooking. 



Gasoline is used to generate 

 the power necessary for the 

 operation of automobiles and 

 other motor-driven machines. 



Naphtha is used to supply 

 light, and as a cooking fuel. 



Fuel oil is used in fur- 

 naces, kitchen ranges, and 

 some types of motors. 



Alcohol, another liquid 

 fuel, is used to some extent in 

 laboratories to produce heat. 



Gaseous Fuels. The 

 gaseous fuels, coal gas, water 

 gas, gasoline gas, acetylene 

 gas, and natural gas are ex- 

 tensively used. Coal gas is 

 produced by distilling soft coal 

 in retorts from which all air is 

 excluded. The bright flame 

 with which coal gas burns is 

 due to the presence in it of 

 hydrocarbons. Water gas is a 

 mixture of carbon monoxide 

 and hydrogen. It is used for 

 lighting purposes in some 

 places, after some form of 



Rock pock?ts u^der"h7rnh r> sometimes hydrocarbon has been added to 



it to render the flame lumi- 

 nous. Gasoline gas is a mix- 

 ture of air and gasoline vapor. Acetylene gas is generated 

 from calcium carbide and water. The gas is allowed to escape 



International Newsreel. 



AN OIL GUSHER 



contain natural gas and oil. When piped, 

 the gas pressure may drive the oil to the 

 surface with tremendous force. 



