Fluid introduction
The earliest examples of the use of oil as a fuel for firing steam locomotives were not in any way the result of carefully pre-planned experiments. In fact, the first came about as the result of a geological feature, when deposits of crude oil were found in the Caucasus region of southern Russia in the 1870s. The Grazi & Tsaritsyn Railway had been built to open up the region and latterly to transport this new resource, and between 1874 and 1884 the motive power was under the supervision of the enterprising English engineer Thomas Urquhart. In a paper presented to the Institute of Mechanical Engineers in 18951 he described how he had converted locomotives to burn ‘petroleum refuse’ – crude oil after the kerosene element had been removed either deliberately or by evaporation from ‘oil lakes’ formed due to uncontrolled ‘gushers’. One hundred locomotives in total were converted, made up of thirteen ‘passenger’ engines, 27 eightcoupled and 60 six-coupled freight examples.2 The oil was sprayed into the otherwise unmodified firebox by a jet of high pressure steam and the author did not hide the fact that the fireman's job was complicated, because of the need to not only regulate the oil/steam jet but also the supply of air for combustion, by a combination of using the ashpan dampers, the variable blastpipe apparatus and a shutter on the funnel itself.
Urqhart described m detail how he conducted comparative trials between oilburning locomotives and their coal-burning equivalents over the undulating 97-mile line between Tsaritsyn and Crostago in both summer and winter conditions. Haulage capacity was comparable and the ‘oilers’ had the great advantage of not throwing sparks, but the big economic benefits were in running and maintenance costs. And, of course, having a very low-cost source of the fuel itself. He admitted to his UK audience that this probably made his experience irrelevant to them, though he believed that it might be worth exploring for underground railways like the recently opened Metropolitan Railway in London, where sulphurous fumes from coal-burning were keeping passengers away.
The first example of oil-firing in the UK came about from the need to dispose of a noxious by-product of ‘oil-gas’ production for use in railway carriage lighting. This gas could be stored and transported under pressure in steel cylinders and it burnt with a light that was six-times brighter than town gas, which was a huge improvement on the smelly oil-lamps then in use. In 1877 the Great Eastern Railway was the second in this country – after the Metropolitan – to invest in a German Pintsch process plant at Stratford for producing oilgas from naphtha, a liquid by-product from early oil refineries.3 In the final stages of this distillation process, the gas produced was passed through circulating water ‘scrubbers’, resulting in the deposit of athe Chief Mechanical Engineer James Holden was asked to find a practical way of disposing of this nuisance and in the light of Urqhart's experience he started devising methods of burning it, initially in stationary boilers but before long in a series locomotives.
