John Crawley continues his much-acclaimed series that looks at early Burrell products, drawing on his personal archive.

The Heavy Motor Car Act was passed in 1904. Until then the law had required that two men were needed on the footplate when travelling on the highway.

This new legislation permitted the engine to be under the control of one man, provided that the unladen weight of the engine didn’t exceed five tons and that the speed did not exceed 5mph.
Burrell’s first tractor was No 2787 built on Monday 18 December 1905. A description of this engine, along with an illustration, is given in The Engineer dated Friday 10 August 1906. In this illustration it has a single cylinder, which is what has always been quoted, and it would seem strange that a reporter on such a journal would get it wrong, but I quote: “The engine is of the compound reversing type placed on top of the boiler. The latter is of the usual traction engine pattern but the fire tubes are curved. They are 25 in number and 13/4in in diameter. The boiler is designed for a working pressure of 175psi and the feed water is supplied by an independent steam pump.

“An injector is also provided, the water for which is gravity-fed. The steering gear is different from the usual practice. A worm on the steering rod operates a worm wheel on a vertical shaft on the side of the smokebox and on a level with the centre line of the boiler. This vertical shaft carries at its lower end a pinion which gears with a spur wheel attached to the front axle.

“The weight of the engine is given as 4 tons 171/2cwt.”
The steering layout can be seen in Fig. 1. The first 11 tractors were fitted with this improved type of steering but the Thetford drawing office had not allowed for the backlash that would arise from the badly-rutted roads, the result of which was fractured teeth in the gearing.

End of the On-line article.
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