steadiness in running, and this class has also double bearings to the driving wheels, thus entailing greater security in case of the facture of a crank axle. The general adoption of cabs on the foot-plate for the men is another improvement of late introduction, although at first not universally appreciated by those for whose comfort it was designed--"I felt as if I was in my coffin," said an old driver when asked how he liked the new shelter. Mild steel fire-boxes, which have been employed in America, are not in favor here, copper being universally used; they have been tried on the Caledonian, Great Southern and Western, North London, and North-Western, and were found not to succeed. Brake blocks of cast iron have now generally superseded wood; steel is being more and more used, especially on the North Western. There is less use of brasswork for domes and fittings, although it is claimed for brass that it looks brighter and can easily be kept clean. There is greater simplicity of design generally, and the universal substitution of coal as coke for fuel, with its consequent economy; and last, but not least, the adoption of standard types of engines, are among the changes which have taken place in locomotive practice during the past quarter of a century. [Illustration: FIG. 8.--LONDON, CHATHAM, & DOVER RAILWAY.] [Illustration: FIG. 9.--GREAT EASTERN RAILWAY.] [Illustration: FIG. 10.--MANCHESTER, SHEFFIELD, AND LINCOLNSHIRE RAILWAY.] Having now reviewed, as far as the limits of this paper will allow, the locomotive practice of the present day, the author would in conclusion draw attention to what may possibly be one course of locomotive development in the future. Time is money, and it may be in the coming years that a demand will arise for faster means of transit than that which we possess at present. How can we meet it? With our railways laid out with the curves and gradients existing, and with our national gauge, and our present type of locomotive, no great advance in speed is very probable; the mean speed of express trains is about fifty miles an hour, and to take an average train of 200 tons weight at this speed over a level line requires between 650 and 700 effective horse-power, within the compass of the best engines of the present day. But if instead of fifty miles an hour seventy is required, an entirely different state of things obtains. Taking a train of 100 tons, with engine and tender weighing 75 tons, or 175 tons gross, the first question to determine will be the train resistance, and with reference to this we much want careful experiments on the subject, like those which Sir Daniel Gooch made in 1848, on the Bristol and Exeter Railway, which are even now the standard authority; the general use of oil axle-boxes and long bogie coaches, irrespective of other improvements, would render this course desirable. With regard to the former, they appear to run with less friction, but are heavier to start, oil boxes in some