A lifetime in LIMESTONE

IN 1929, just three years after the merger that resulted in the formation of Imperial Chemical Industries Ltd, the new company began development of Tunstead Quarry, near Buxton in Derbyshire. Destined to become the largest limestone quarry in Europe, the new complex incorporated both a crushing plant and lime kilns, thereby increasing production whilst still allowing the closure of anumber of older quarries.

However, probably the single most important reason for the development of Tunstead was the need to guarantee a reliable long-term supply of high-purity limestone for the company’s chemical works at Northwich, located 25 miles to the west at the heart of the Cheshire saltfield.

With developments at Tunstead underway, thoughts turned to transport. Until this time, Brunner Mond Ltd, the ICI subsidiary that owned the works in Northwich, had relied upon a fleet of ‘standard’ 12-ton mineral wagons for deliveries of limestone. While relatively recently built, they must, nevertheless, have been far from ideal given the volume of traffic being handled.

Unloading would have involved uncoupling each individual vehicle, shunting it onto the wagon tippler, securing it in position and tipping to discharge the load before then marshalling the empties for return to the quarry. With trains loading up to 50 wagons, this was an extremely laborious and time-consuming process.

Prewar hoppers

The solution was a 43½-ton bogie hopper wagon that was developed in consultation between ICI, the railway companies and Charles Roberts & Co Ltd, the wagon builder based at Horbury Junction, near Wakefield.

Not only would the new design carry a load that was three and a half times greater than the wagons