Читать книгу The North York Moors. 50 walks in the National Park онлайн

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Whitby and Whitby Abbey as seen from the Whalebone Arch (Walk 44)

North York Moors industries

Alum

Throughout the North York Moors National Park huge piles of flaky pink shale have been dumped on the landscape, sometimes along the western fringes of the Cleveland Hills, but more especially along the coast. These are the remains of a large-scale chemical industry that thrived from 1600 to 1870. The hard-won prize was alum: a salt that could be extracted from certain beds of shale through a time-consuming process.

Wherever the shale occurred, it was extensively quarried. Millions of tons were cut, changing the shape of the landscape, especially along the coast. Wood, and in later years coal, was layered with the shale, and huge piles were set on fire and kept burning for months, sometimes even a whole year. The burnt shale was then soaked in huge tanks of water, a process known as leaching. Afterwards, the water was drawn off and boiled, which required more wood and coal, as well as being treated with such odious substances as human urine, brought from as far away as London. As crystals of precious alum began to form, the process was completed with a purification stage before the end product was packed for dispatch.