https://www.agron.iastate.edu/glsi/2018/04/15/william-smiths-1815-delineation-of-the-strata-of-england-and-wales-with-part-of-scotland-varieties-of-soil-according-to-the-variations-in-the-substrata/
William Smith’s 1815 Delineation of the Strata of England and Wales with Part of Scotland: …Varieties of Soil According to the Variations in the Substrata (2018 EGU General Assembly)