223.    ---------------. [ BERTHELOT, C.] [Large Gas Generators for the Production of Water Gas.]  Génie Civil, vol. 109, 1936, pp. 103-106; Chem. Abs., vol. 30, 1936, p. 7308.

                 Drawings and description of the Winkler and Didier systems are given.  The thermal efficiency of the latter plant is about 75% and the total cost about $0.15/1,000 cu. ft. of gas using lignite briquettes at $4.00/ton.