Rail chair, Silkstone Waggonway, cast iron chair for plate rail, shallow chair with central fixing hole, marked "2". Dimensions 223x190x51mm. Central fixing hole is 1 1/2" in diameter. Thickness of base rises towards centre, 3/4" to 1 1/8" from both directions. Ribs to retain plate are curved in plan, from 5" to 5 1/2", suggesting a 1 in 5 crossing (but not necessarily so). Precise purpose not obvious.