Railways come in many sizes, and are usually measured by their gauge: the distance between the rails. The Perrygrove railway is laid to a gauge of 15 inches – about 381 mm. This page tells you why.
As the gauge of a railway reduces so the stability of vehicles decreases. In about 1874 a country gentleman called Sir Arthur Percival Heywood started experiments to find the narrowest gauge ‘possessing the necessary stability for practical use’. Sir Arthur came from a wealthy family and his father took a perverse pride in bringing his sons up to pursue no profession. This meant that although Sir Arthur graduated in mechanical engineering at Cambridge he had to remain an amateur and carry out his experiments at home on his miniature estate at Duffield Bank just north of Derby. He eventually developed one of the finest private railways and workshops there has ever been.
Sir Arthur was working in the era before the internal combustion engine when the practical alternative to a railway was usually a horse and cart. He looked for the minimum gauge that could be used to serve the needs of an agricultural district or supply troops in the field.
He settled on 15 inches and was able to show that this very narrow gauge did indeed achieve the objective he had set. Sadly, the only opportunity he had to put his ideas into practice personally was when the Duke of Westminster commissioned him to construct an estate railway at Eaton Hall in Cheshire, in 1895. Most subsequent 15 inch gauge railways have been built to carry passengers for pleasure, but the Eaton Hall line was built for carrying coal, timber and bricks; and the Ravenglass & Eskdale line in Cumbria carried thousands of tons of granite for many years. The very closely similar gauge of 40cm was used in many industrial locations including Martin Earle’s cement works near Rochester. There was considerable use of both 15″ and 40cm gauges on the continent of Europe. The best description of these developments is at Gn15.info (follow the links to ‘Real 15″ lines’ and ‘Notes on the Early History of 15 inch Gauge Prototypes by Peter Kuntze’).
We wanted to use the 15” gauge at Perrygrove and we were able to do so because the Exmoor Steam Railway offered to build us a suitable steam locomotive – Spirit of Adventure was the result. From this grew the idea of creating a Heywood style railway, but it was our friend James Waterfield who made this a reality by using Perrygrove as a base for Ursula and his re-creations of other Heywood rolling stock. It is through the efforts of enthusiasts like James that the Heywood tradition is being revived.
Gradually, in partnership with James, Richard Pennington, and others, a collection of original artefacts from Heywood’s lines and other examples of very small railways has been assembled. Many of these things are on display at Perrygrove, but sometimes they are exhibited elsewhere, so please do check before setting out on a journey to see a particular item.