The Diesel-electric Locomotive.

Apart from the high cost of power, an obstacle to the speedy conversion to electric traction of the Home railways is the costly nature of transmission lines, substations, conductors, and other equipment. In the endeavour to overcome this obstacle, much attention is now being turned to the possibilities of Diesel-electric traction.

Diesel-electric services possess all the marked advantages of electric haulage. They may be built up and expanded gradually as capital becomes available and traffic increases, and they may be extended outwards to any desired mileage to meet occasional demand. They render high speed running easy of accomplishment, and increase, to a marked degree, track capacity. Under Diesel-electric operation, trains may be operated on the familiar multiple-unit arrangement, and altogether this form of working offers many attractions.

The Diesel-electric locomotive is well adapted to main-line operation, while in branch-line working Diesel-electric rail-cars offer a quick and economical train unit, comparable with the existing steam rail-cars employed in Britain and New Zealand. A new 250 h.p. Armstrong-Sulzer Diesel-electric rail-car recently developed at Home can, it is claimed, be operated for from threepence to fivepence less per train mile than existing steam rail-cars with 100 h.p. boilers, calculating coal at sixteen shillings and Diesel oil at ninety shillings per ton. In Switzerland, Diesel-electric traction is being employed to a considerable extent. On the Appen-zell Railway, passenger operation is being page 19 successfully and economically performed by means of rail-cars fitted with 250 h.p. 6-cylinder Sulzer airless injection Diesel engines, while developments in the employment of Diesel-electric traction are also proceeding in Germany.