Built in 1925 by Marshall Sons & Co. Ltd. Britannia Iron Works, Gainsborough, Lincs. Supplied new to the Parish of St Helier, and was in regular use until well after the second world war.
Marshalls have been in business since 1847, building traction engines from 1876 onwards, and rollers from 1894. Between 1900 and 1914 rollers were a major part of production. Travelling speed was 4 m.p.h., rolling 2 m.p.h. or less. With a roller it is important that it does not ‘dwell’ too long at the end of each roll (otherwise it will sink in). For this reason Marshall's fitted an engine capable of rapid reversal. It consists of two separate single cylinders placed side by side, but with the cranks set at 90˚ to each other. In this way four equal overlapping thrusts are given to the crankshaft in each revolution and it will start forwards or backwards from any position.
The piston valves are operated by Marshall's own adaption of Hackworths radial valve gear of 1854, and this interesting gear (being outside the cranks) can be clearly seen.
The engine is also fitted with Marshalls stayless firebox crown. Instead of stays, the crown, or top of the firebox is pressed out in a cruciform shape to increase rigidity – a principle similar to that employed in corrugated iron sheets.
Finally, to remove a bad road surface prior to resurfacing, the engine is fitted with an ALLEN ‘patent scarifier’ – seen behind the offside rear wheel. This consists of a vertically adjustable frame in which large chisels are fixed; these can be lowered to bite into the road surface as the roller moves forward.
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