Theodolite-wielding geodesists

At the Independent, Jonathan Brown on the history of the Ordnance Survey as its maps go online:

According to Dr Richard Oliver's A Short History of the Ordnance Survey of Great Britain, the first modern maps took shape between 1747 and 1755. Their instigator was an ambitious military officer named Colonel David Watson, who served with the Army and also the Engineers of the Board of Ordnance. The painstaking work was carried out by the Lanarkshire-born surveyor William Roy, who went on to become the father of modern cartography, and the pioneering water colourist Paul Sandby, who helped turn the first maps into beautifully realised artworks. It was a primitive process by modern satellite-driven standards. The contour line was yet to be invented, and all distances were measured by 66ft lengths of chain.