Fifteen-inch gauge railway
Fifteen-inch gauge railways were pioneered by Sir Arthur Percival Heywood who was interested in what he termed a minimum gauge railway for use as estate railways or to be easy to lay on, for instance, a battlefield. In 1874, he described the principle behind it as used for his Duffield Bank Railway, distinguishing it from a "Narrow Gauge" railway. Having previously built a small railway of 9 in (229 mm) gauge, he settled on 15 in (381 mm) gauge as the minimum that he felt was practical.
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