390 F. H. OLIPHANT 



tests have fully demonstrated that when ordinary care is taken 

 in burning natural gas under boilers in actual service, 1 cubic 

 foot of natural gas will do the work equivalent to the evapo- 

 ration of one pound of water at and above 212° F. Since 20 

 cubic feet of ordinary natural gas weigh one pound, one pound 

 of natural gas will evaporate 20 pounds of water, while, luider 

 similar conditions, one pound of petroleum will evaporate only 

 16 pounds of water, and one pound of good coal will evaporate 

 but 10 pounds of water; therefore 10 cubic feet of gas is equal to 

 one pound of coal, or 20,000 cubic feet will equal one ton of coal. 

 Only two articles have been made directly from natural 

 gas; they are lampblack and gas coke. Lampblack is still 

 n-Lade, but gas coke ceased to become a product when natural 

 gas as a fuel was consumed in an economical manner. In 

 isolated districts, where it is difficult to convey the natural gas 

 to market, numerous wells have been made x^rofitable by the 

 conversion of the gas into lampblack. The process is ex- 

 tremely wasteful, as the amount of carbon actually secured is 

 probably not more than one twentieth of the carbon contained 

 in the gas consumed. In the manufacture of lampblack or 

 carbon black a great number of small jets are made to impinge 

 upon a pipe, through which there is a circulation of water to 

 keep it cold. The carbon is deposited on the pipes in very 

 thin films and accumulates very slowly. Automatic scrapers 

 and brushes are arranged to collect the deposit, so that the 

 flames can have the clean, cold surface of the pipes upon which 

 to deposit a fresh supply. The lampblack thus secured is 

 said to be the very fiiiest, and is used extensively at home 

 and abroad. 



Gas coke is a product of the imperfect combustion of 

 natural gas when the unconsumed portion is highly heated. 

 Under such condition the gas is decomposed and pure carbon is 

 deposited. Generally the deposit was obtained from the fire 

 boxes of the heating furnaces used in the manufacture of 

 wrought iron, and found a ready sale for use in the manufacture 

 of electric light carbons. It is similar in appearance to the 

 coke formed from coal, and has a metallic ring when struck 

 with a hammer. 



The pressure in most of the original fields at first was ample 



