The Reader of Rocks

At the same time, Smith worked out a table of succession for the sedimentary rocks, listing the series of strata laid down, in chronological order, from the oldest, "Granite, Sienite and Gneiss," to the most recent, "London clay." There had been geological maps before, based on rocks found at the surface, but Smith's breakthrough came with his use of fossils, found in different layers and at different depths, to identify the strata and suggest their distribution below the ground. As Douglas Palmer notes in his introduction to Strata, Smith had the luck to be in the right place at the right time: almost a century before, a house on the estate had belonged to John Strachey, "An Oxford-educated country squire and landowner who developed an interest in geology and its use in the search for coal." Strachey's 1719 drawing of a section through the Somerset coalfield provided Smith's first revelation of the layers of sedimentary rocks and their fossils. In late January 1794, his map of the area was engraved by John Cary, whose New and Correct English Atlas of 1787 was a standard reference work, and who would later engrave all Smith's geological maps. On Bedford's Woburn estate, Smith became friendly with the duke's agent, the mineral surveyor John Farey, who became his stout supporter in his work as a "Well-sinker," which John Mather describes in an intriguing essay, one of seven in Strata on different aspects of Smith's career. In his essay on Smith as a cartographer, Tom Sharpe suggests that Banks may have helped the spread of Smith's ideas about fossils as stratigraphic signifiers abroad as well as at home. Finally, recognition came: in 1831 a new generation at the Geological Society awarded Smith the society's first Wollaston Medal. In his speech the president of the society, Adam Sedgwick-long an admirer-called Smith the "Father of English Geology." In one of his last projects he served on the commission touring England and Scotland to find freestone suitable for the new Houses of Parliament.