Thomas Telford's life was extraordinary: born in the Lowlands of Scotland, where his father worked as a shepherd, he ended his days as the most revered engineer in the world, known punningly as "The Colossus of Roads". He was responsible for some of the great works of the age, such as the suspension bridge across the Menai Straits and the mighty Pontcysyllte aqueduct. He built some of the best roads seen in Britain since the days of the Romans and...