Pedrail wheel

The tread consists of a number of rubber shod feet which are connected by ball-and-socket joints to the ends of sliding spokes.

Each spoke has attached to it a small roller which in its turn runs under a short pivoted rail controlled by a powerful set of springs.

G. Wells, in his short story The Land Ironclads, published in The Strand Magazine in December 1903, described the use of large, armoured cross-country vehicles, armed with automatic rifles and moving on pedrail wheels, to break through a system of fortified trenches, disrupting the defence and clearing the way for an infantry advance: They were essentially long, narrow and very strong steel frameworks carrying the engines, and borne upon eight pairs of big pedrail wheels, each about ten feet in diameter, each a driving wheel and set upon long axles free to swivel round a common axis.

Diplock's version of an endless track was not designed until some ten years after the publication of Wells' story.

[5] It was a complicated and high-maintenance system, and in 1914 Diplock eventually produced a version on a simpler, single wide track.

An advanced design pedrail wheel climbing stairs.
1904 illustration of H. G. Wells ' December 1903 The Land Ironclads , showing huge ironclad land vessels, equipped with pedrail wheels.