522 CEMENTS, LIMES, AND PLASTERS. 



Lathbury, B. B., and Spackman, H. S. The Lathbury and Spackman coal- 

 drier. The Rotary Kiln, pp. 15p-151. 1902. 



Anon. Powdered fuel for boiler-furnaces at the Alpha Cement Co.'s works, 

 Alpha, N. J. Engineering News, 1897. 



Anon. A new system for burning powdered coal. Engineering News, vol. 48, 

 p. 548. Dec. 25, 1902. 



Oil. 



Petroleum was early used in New York and Pennsylvania as a fuel 

 for rotary kilns, but was gradually supplanted by powdered coal. At 

 present no Eastern plants use oil as fuel. In the West, however, where 

 good gas coals are unobtainable at reasonable prices, oil is now in use 

 at four Portland-cement plants. 



From 11 to 14 gallons of oil are required in Western practice to 

 burn a barrel of cement ; a safe estimate is that one barrel of oil (42 gal- 

 lons) will burn three barrels of cement. Oil may, therefore, be com- 

 pared with coal, in the rotary kiln, on the basis of 1 gallon of oil being 

 equal in effect to 10 Ibs. of coal. 



List of references on petroleum. The papers on petroleum contained 

 in the following list are of interest either as containing discussions of the 

 fuel value of petroleum, or as describing certain oil fields whose product 

 is at present utilized in Portland-cement manufacture. 



Eldridge, G. H. The Florence oil field, Colorado. Trans. Amer. Inst. Mining 

 Engrs., vol. 20, pp. 442-462. 1892. 



Eldridge, G. H. The petroleum fields of California. Bulletin 213, U. S. 

 Geological Survey, pp. 306-321. 1903. 



Fenneman, N. M. The Boulder, Colorado, oil field. Bulletin 213, U. S. Geolog- 

 ical Survey, pp. 322-332. 1903. 



Peckham, S. F. Petroleum in southern California. Science, vol. 23, pp. 74- 

 75. 1894. 



Anon. Fuel oil on the Pacific Coast. Engineering and Mining Journal, 

 Dec. 20, 1902. 



Natural Gas. 



Use of natural gas in kilns. Natural gas is at present used as a 

 kiln fuel in several Kansas plants and at one in Ohio. As a kiln fuel 

 it is satisfactory enough, giving as much results per B.T.U. as does 

 a good coal. Apparently, however, a gas-fired kiln cannot be pushed 

 as hard as a kiln using coal, though the data are insufficient to give 

 any decisive evidence on this point. A recent report on a Western 

 cement proposition states that the natural gas to be used in the kilns 



