. Electric railway journal . ng, asthe instrument has just been placed on the market. A third measuring instrument of almost equal importance,but for measuring the amount of coal fed to each boiler,has also been developed, and is illustrated. It consistsessentially of a propeller of large pitch capable of beingslipped inside a downtake coal pipe so that the coal inflowing down from the overhead bunkers or conveyor turnsthe propeller blades and by suitable integrating mechanismindicates on a dial the coal used in any particular periodIndications are that the results obtained are sufficientlyacc
. Electric railway journal . ng, asthe instrument has just been placed on the market. A third measuring instrument of almost equal importance,but for measuring the amount of coal fed to each boiler,has also been developed, and is illustrated. It consistsessentially of a propeller of large pitch capable of beingslipped inside a downtake coal pipe so that the coal inflowing down from the overhead bunkers or conveyor turnsthe propeller blades and by suitable integrating mechanismindicates on a dial the coal used in any particular periodIndications are that the results obtained are sufficientlyaccurate for comparative purposes. In the furnace the principal development seems to be inthe intelligent use of forced draft in order to obtain highrates of combustion when required. In most railway plantsthe ratio of one hour peak to average 24-hour load isapproximately two to one, and the ratio of minimum hourlyload to average 24-hour load about four or five to one, ora ratio of eight or ten to one from maximum hour to mini-. Power Generation—Steam Meter and Coal Meter mum hour. To meet this enormous variation of load in aneconomical manner, taking into consideration not only oper-ating and maintenance charges, but also fixed charges, thebest solution seems to be to design the boiler room equip-ment for maximum operating economy at the average loadof the plant, and be prepared to sacrifice some slight lossin efficiency at the higher and lower loads. Severalmethods of doing this are available, the most obvious onebeing to install two stokers, or grates, under each boiler,so that one may be banked during the lighter loads. This 782 ELECTRIC RAILWAY JOURNAL. [Vol. XXXVIII, No. 15C. will give a range of steaming of almost two to one asrequired by the load curve. A second method, which hassome very attractive features, but is as yet incompletelydeveloped, is the use of oil in burners protected by thebridge wall from the grate or stoker on which coal is beingburned. There seems to
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