The Map That Changed The World
By Simon Winchester
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It’s difficult to imagine what our forebears made of the world around them - or, in the case of geology, the world underneath them. In 1658, James Ussher, Bishop of Armagh, announced that God began the act of creation at 9am on Monday, October 23, 4004 BC, wrapping the job up in time for tea on the following Saturday.

The idea that the process was infinitely more gradual had not been envisaged, and the now familiar mechanisms involved - the heaving up and grinding down of mountains and the painfully slow evolution of species - had yet to be described by the time the industrial revolution got under way. Fortunately, that revolution, with its appetite for coal and iron, was to take men with keen eyes and questioning minds deep into the ground. And such a man was William Smith, the subject of Simon Winchester’s book.

A man of humble origins, Smith was working as a surveyor in a Somerset coal mine when he became fascinated by the sequence of rock strata visible in the rough-hewn walls. What if that vertical sequence of layers were repeated elsewhere? It was his next job - as surveyor to a canal company - that gave Smith the opportunity to test his theory.

Slicing through the Somerset countryside, he realised that the various strata could be identified precisely by the fossils they contained. It was in 1815, after a decade and a half of single-handed labour, that Smith finally published his masterpiece - a 50-foot-square, hand-coloured map of the geology of England and Wales.

For many readers - and, no doubt, television producers, for it’s difficult to avoid seeing this as a made-for-television drama - it’s the familiar human story of triumph over obscurity that will appeal.

A longer version of this review appears in this week’s Friday magazine