286 FUEL AND LIGHT 



Bituminous coal is soft coal much of which burns freely, giving 

 off volumes of pitchy smoke. It is found in the eastern and 

 western parts of the United States, and also in Missouri, Arkansas, 

 Ohio, Indiana, Illinois, Kansas, and Oklahoma. 



Cannel coal is a variety of bituminous coal. It is much harder 

 than ordinary bituminous coal and burns with but little smoke. 

 It is found in few localities and largely preferred for blacksmithing. 



Anthracite is the hardest and most compact coal known in this 

 country. It is almost free from hydrocarbons or oils and burns 

 with a slight blue flame and with strong heat. On account of its 

 hardness it can be handled without smutting one's hands, and when 

 placed in the stove it burns for a long time. If the stove is filled 

 with anthracite in the morning, usually the supply will last all 

 day without replenishing. Nearly all of the anthracite used in 

 the United States is mined in the eastern part of Pennsylvania, and 

 on account of its limited area of production it is generally some- 

 what expensive. 



Coke is coal which has been heated in ovens or kilns from which 

 the air has been partially excluded. The heating is continued 

 until all the hydrocarbons have been burned or driven off and a 

 light substance resembling charcoal remains. On account of its 

 lightness and cleanliness it makes a very satisfactory fuel. 



Coal gas is a very important fuel in cities and is obtained by 

 distilling coal. It is stored in a large tank and piped from this 

 to the places where it is to be used. This gas is also used for 

 lighting purposes. 



Water gas is prepared by passing water in the form of super- 

 heated steam over glowing anthracite coal. The resulting gas 

 contains equal volumes of carbon monoxide and free hydrogen. 

 It is enriched by the addition of petroleum vapor and is used for 

 both lighting and heating.' 



Natural gas is obtained by boring to a considerable depth 

 into the earth and is found in various parts of the United States. 

 Profitable gas wells have been sunk in California, in the Beau- 

 mont district in Texas, in Oklahoma, Louisiana, western Pennsyl- 

 vania, West Virginia, Central Ohio, and some parts of Indiana. 



This gas is used for heating, lighting, and cooking, and its use 

 is very satisfactory. On account of its freedom from sulphur 



