High-power Steam Locomotives in Britain.

Electrification developments may everywhere confidently be looked for in the next few years, but there will, admittedly, for a decade or two continue to be a demand for steam locomotives of high power for drawing long-distance passenger and freight trains. In Britain many new high-power steam locomotives have been introduced recently, and in a paper read the other day by Mr. H. N. Gresley, Chief Mechanical Engineer of the L. and N.E. Railway, before the Institution of Mechanical Engineers, progress in high-pressure locomotive design was very ably reviewed.

Pointing out that the purpose of the novel forms of locomotive recently introduced was to effect economy, principally in fuel, Mr. Gresley dwelt upon the importance of keeping maintenance costs down, the expense incurred in maintaining locomotives being equal to the cost of the great quantity of coal consumed. There was an immense field for economy if both cost of fuel and maintenance could be reduced. While high steam pressure gave greater fuel economy, it demanded complication in design, and care had to be taken that the economies in fuel were not absorbed in the increased cost of maintenance of the boiler and the machine as a whole. Simplicity of design was an important factor: simplicity usually spelt accessibility. In all the latest high-pressure locomotives reciprocating pistons had been adopted, this form of conversion of energy appearing the most advantageous for meeting all conditions which a locomotive had to fulfil. Owing to the high range of temperature and the consequent losses by condensation in a simple engine, the use of a compound, or “Uniflow” system, was essential. It was interesting to note that in the high-pressure locomotives produced at Home within the page 48 past five years, two, three and four-cylinder compounds had all been adopted.