THE advent of fuel oil has become an important factor in railway loc6motion. It is estimated by the United States Geological Survey that from 20,000,-000 to 25,000,000 tons of coal per annum are replaced by oil, and a large part of this is used by locomotives. In this connection there is interest in a statement which will appear in the forthcoming petroleum report of the Geological Survey showing the extent to which oil is used as a locomotive fuel. The author of this report, David T. Day, computes the total length of railway lines operated during 1910 with petroleum as a fuel to be 21,075 miles, a trackage practically equivalent to that of fve transcontinental lines stretch- ing across the United States from ocean to ocean. The number of barrels of fuel oil used by the railroads (42 gallons per barrel) was 24,526,883. This ineludes 768.762 barrels used by the railroads as fuel other than in locomotives. The total number of miles run by oil burning engines during the year was 88,318.947. This would have carried one engine or train around the world approximately 3,530 times. The advantages of oil as locomotive fuel over coal have been stated by Eugene McAulife as many. They include decreased cost of handling oil from cars to engines, with practically no loss by depreciation due to such handling; evaporation losses sufered by coal as not applying to oil; saving of time at terminals for engine cleaning and providing increased mileage per engine, the oil capaeity of the tender being about 150 per cent of that of coal; freedom from physica 1 failure of fremen in extreme hot weather; delivery of oil being unafected by labor conditions, the eoal situation necessitating in some instances heavy storage at great expense; greater cleanliness in handling all passenger trains, lack of smoke and immunity from right-of-way forest fres. The expense of equipping the average locomotive to burn oil is about $800, and the cost of large steel storage tanks is about 25 cents per barrel: but the necessary terminal facilities for handling oil eost 50 per cent less than the amount required to handle coal.