GREAT STEAM ENGINEERS OF THE NINETEENTH CENTURY PART SEVEN: THE 1880s

Francis Webb had become chief mechanical engineer on the London & North Western Railway in 1871 and was a prolific locomotive designer. He was also responsible for the remodelling of Crewe station, which involved building four tracks in underpasses on the west side of the station so freight trains could bypass the station.

Webb came up with numerous inventions and received more than 80 patents. He was vice-president of the Institution of Civil Engineers and the Institution of Mechanical Engineers.

Webb took a great interest in local politics – he was an alderman on the Crewe Town Council and was mayor twice. He was also an alderman on Cheshire County Council.

Between 1881 and 1897, Crewe built 300 of Webb’s Coal Tanks, an 0-6-2T version of his standard 17in Coal Engine 0-6-0, with the same cheaply-produced cast iron wheels and H-section spokes as the tender engines.

The 250th Coal Tank to be built, No. 1054 entered service in 1888 and became one of 64 inherited by BR in 1948 and the last survivor; withdrawn from Abergavenny shed in 1958.

A group of determined enthusiasts headed by Max Dunn, the former shedmaster at Bangor, organised an appeal to raise funds to buy No. 1054. The appeal was successful and the engine was purchased for preservation. It is now in service and in the care of the Bahamas Locomotive Society, based at Ingrow on the Keighley & Worth Valley Railway.

Also on the plus side, Webb designed the ‘Improved’ or ‘Renewed’ Precedent express 2-4-0 and 160 were built at Crewe between 1887 and 1902. They were officially ‘renewals’ of the original Precedents and some Newtons for accounting purposes. The ‘new’ engines retained their names and already haphazard numbers, and eventually they acquired the nickname ‘Jumbos’.

Webb is well-known as having been an early advocate of compounding – a compound locomotive is a steam locomotive where steam is expanded in two or more stages. It was more popular in ships in which two and even three stages were used.

Compound locomotives employ a high-pressure cylinder group before passing the steam to a second, low-pressure group. The purpose of compounding is to extract the maximum power and efficiency from the steam raised in the boiler, simply by using it more than once before it is exhausted out of the chimney. There had been experiments from the early days of steam, starting with two-cylinder ‘cross-compound’ designs, with one high-pressure and one low-pressure cylinder.

The cross-compound can be difficult to start and can become unbalanced. This led to various variations on the compound principle with both three and four-cylinder designs. The first successful compound locomotives were three small two-cylinder 0-4-2Ts built in 1876 to the design of the Swiss-born engineer Anatole