Engineering Wonders of the World
Volume I

182 ENGINEERING WONDERS OF THE WORLD. MARC ISAMBARD BRUNEL. (From the Painting by Northcote in the National Portrait Gallery. Photo, Rischgitz Collection.) Early Schemes for Tunnelling the Thames. tions of electricity for lighting and power pur- poses, highly-developed hydraulic and steam machinery, and a large number of prece- dents. His work is at times arduous enough —witness the Blackwall Tunnel and the New York subaqueous bores—yet he will readily admit that Brunel’s feat, accomplished when iron linings and pneumatic shields and the electric lamp were not yet invented, and the steam-engine still in its infancy, stands un- surpassed in the annals of tunnelling. Marc Isambard Brunel was a Frenchman by birth, became a citizen of the United States by choice, and died an English knight. The Marc Isambard Brunel. greater part of his life was spent in England, where he busied himself in many useful inventions and a number of engineering works, of which the Thames Tunnel was the last and greatest. The need of easy communication between the two banks of the Thames east of London Bridge had become pressing at the end of the eighteenth century. As the construction of a bridge was out of the question on account of river traffic, engineers of that time gave their serious attention to tunnelling schemes. In 1798 a Mr. Dodd proposed a 900-yard tunnel be- tween Tilbury and Gravesend. In 1802 followed a scheme to join Limehouse and Rotherhithe. A Mr. Vazie sunk a shaft to a depth of 76 feet below high water, and, aided by John Treve- thick, drove a small heading under the Thames for a distance of 1,100 feet. Then the bed of the river gave way, water came in, the money available for the enterprise gave out, and the project had to be abandoned. A vast number of suggestions for carrying the matter through were made ; but the fifty-nine selected for consideration by eminent authorities wilted under the verdict that an underground tunnel which would be “ useful to the public and beneficial to the adventurers ” was imprac- ticable. When fifteen years had passed away, Brunel came forward with a proposal for driving a tunnel with the help of a shield, which should hold up the ground in front during excavation and allow Brunel’s brickwork to be put in behind. Proposal. The tunnel was to have a rectangular section, 38 feet wide and 22j feet high over all, and contain two parallel road- ways separated by a wall pierced with arch openings. The dimensions alone denoted a bold scheme —so bold that some critics declared it to be beyond the powers of a man who had had no experience in mining. Brunel replied by explaining his shield method in detail. Scepticism gave way to enthusiasm, and at a meeting held on Feb- ruary 18, 1824, in the City of London Tavern, a company was formed, with a capital of A Tunnel Company formed. £200,000, to