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Richard Beamish, an engineer, tells of the time when he was employed by Isambard Kingdom Brunel and his father, Marc, to work on the Thames Tunnel.
It was 1825 and no one had ever dug a tunnel under a river before.
Beamish wanted to know how this would be achieved and Brunel explained the theory behind the 'Shield', a device that his father, Marc, had invented.
The Shield was a huge metal disc with doors in it, which enabled the workmen to stand on it, open the doors and dig out sections of soil to create the tunnel, while the shield kept the rest of the earth in place.
However, the River Thames contained a lot of sewage and many workmen working underground collapsed from breathing in the fumes and there was a further problem with water constantly entering and flooding the tunnel. On one occasion Isambard Kingdom Brunel himself was caught up in such a flood. He was badly hurt, but he survived; others were not so fortunate.
It was seven years before work resumed on the tunnel and it was finally finished. And, although Isambard Kingdom Brunel never returned to work on the tunnel after he had recovered, he went on to other challenges and even greater achievements...
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