"Crewe and Swindon gave him his training as a locomotive engineer, to such effect that he was appointed at 22 to superintend and manage the Londonderry & Coleraine Railway, though he went shortly afterwards to India to the Bombay & Baroda Railway. 

 

Later (in 1859) he became established as a consulting engineer at 56 Gracechurch Street London E.C. It was during this period that the idea for his patent germinated: Patent No. 1210, for improvements in locomotive engines and boilers, was granted on May 12th 1864. It covered the attainment of high tractive effort, for low axle-loading, with flexibility of wheel-base: the adoption of total adhesion was to increase the "bite" on the rails, in Fairlie's words. The boiler was to be mounted on the centres of two frames resting on the bogies. Provision was also claimed for coupling the bogies directly and for putting wheels under the firebox. A less well-known aspect of the patent was the provision of a second or even third layer of tubes in the boiler, reversing the gas flow to provide extra heating and drying of the steam before it passed to the cylinders. With two sets of tubes, one chimney and blast-pipe are set over the top of the firebox; with the triple tube arrangemnet chimneys are set at each end overt normal smokeboxes. The fire box is undivided. 

 

In the same year Fairlie published a pamphlet ("Locomotive Engines-what they are and what they ought to be"), in which he expounded, by means of a dialogue between an engineer and a writer, the current shortcomings of coventional steam engines-the wasteful need to have a tender for fuel and water, the inadequacy of conventional tank engines for long runs, the problems of using bogies, and the lack of standardisation. Then the writer showed how his patent locomotive would overcome all objections, by the superior steam generating of the boiler, the all-adhesion principle with all fuel carried on the engine, the ability to traverse sharp curves with reduced friction, the abolition of turn-tables, and the reduction of capital and maintenance expenses by standardisation of parts. 

 

It has been said that Fairlie's idea was not original, for one of the competitors in the Semmering trials of 1851 was the "Seraing", by the Belgian firm of Cockerill; this engine had all the features of the devoloped Fairlie locomotive. But the "Seraing" did not initiate a trend, wheras Fairlie developed his patent into engines that were built and sold all over the world. The 1864 pamplet suggests that he may have been more influenced by Sturrock's attempts to increase tractive power on the G.N.R. (Archibald Sturrock was locomotive engineer of the Great Northern Railway 1850-1866 )with his steam tenders, and by the back-to-back tank engines introduced on the Great Indian Peninusula Railway Ghat inclines (near Bombay) from 1856. Another significant feature of this pamphlet is that the emphasis is on engines for broad (7ft) and narrow (standard) gauges; "narrow gauge" in the later sense is not mentioned. However, Fairlie does stress that his engine is not only for main-line heavy traffic, but also for light traffic (using one power bogie only) or for railways in difficult country which would have been unecomic for conventional locomotives. One interesting diagram in the pamphlet is for an "express goods and third-class passenger traffic" engine, an anticipation of the modern mixed-traffic machine. A second patent, No. 3185 of December 9, 1865, proposed a modified engine, the fuel and water being carried on the same chassis as the boiler and cab, but with only one boiler. 

 

M Seymour "The Year of the Fairlie" Railway Magazine September 1969 p490 onwards.