Last updated at 12:12, Thursday, 12 April 2012

AN illustrated talk on the subject “Tower Bridge an Engineering Icon” was given by Philip Wilson at our meeting in the Civic Hall.

Mr Wilson, a Cockermouth Probus Club member, was no stranger to our club having delivered several interesting talks to us over the years.

In medieval times a stone bridge was built across the Thames near the Tower of London and this subsequently had houses erected on it. As it had not been designed to carry the extra load of these houses parts of it regularly collapsed and this led to the well-known song “London Bridge is Falling Down,” a not infrequent occurrence. This was in fact the only Bridge to cross the Thames for many hundreds of years.

In 1876 the City of London Corporation decided to build a new bridge to the east of London Bridge. They initiated a public competition for the design of a Thames crossing and offered a prize of £80,000.

Over 50 designs were submitted to the committee, some from the most famous Engineers of the time like Thomas Telford and Joseph Bazalgette, but the contract was finally awarded, in 1884, to Horace Jones, the City Architect, in collaboration with John Wolfe Barry. Their design most closely met the criteria laid down enabling the uninterrupted passage of small vessels, facilities to allow the passage of tall vessels and easy access for the horse drawn road vehicles of the time and pedestrians.

The design consisted of two steel towers, 213 ft. high, mounted on massive piers sunk into the riverbed. The towers, with a central span of 200 ft, were tied together at high level by two permanent walkways designed to counteract the horizontal forces exerted by the suspended sections of the bridge. The Bridge could be “raised” quite quickly taking approximately one minute. The two side spans were suspension bridges and allowed uninterrupted passage for small vessels. The overall bridge length was some 800 ft.

Construction started in 1886, took eight years to complete and cost £1,184,000 or some £100 million in today’s money. The Bridge was officially opened in 1884 by the future King Edward VII.

The bridge has had some memorable moments. In 1912 Frank McCIean flew a bi-plane between the Towers, in 1952 Albert Gunton drove his double-decker No 78 bus Evil Knievel-like across the partially opened roadway and in 1968 Lt Pollock flew his Hawker Hunter Jet between the Towers. Happily the Bridge was not damaged in World War II although the surrounding area was devastated.

The vote of thanks was proposed by Don Ellam.

The meeting ended with lunch and a celebration of member Len Harrison’s 97th birthday.

First published at 11:58, Thursday, 12 April 2012
Published by http://www.whitehavennews.co.uk