It’s something many of us barely think about getting from A to B. Although in London it can be quite stressful to plan a journey, the fact remains that transport is something that is easy to take for granted. However, it is vital and shapes the way that our city is built and the way it runs.
Despite using the tube everyday, many of us probably do not know about the history and origins of it in depth. I was certainly interested to learn more about it when I took a trip to the London Transport Museum, which has and will play host to various events taking place to mark the 150th anniversary of the underground.
These events include: steam runs of the ex-Metropolitan Railway Steam Locomotive and the Metropolitan Railway Jubilee Carriage, an exhibition of poster art showcasing 150 of the best designs commissioned by the London Underground, and some behind-the-scenes events at the Museum Depot at Acton including, photography, art, design, creative writing and ‘Driver’s seat days’.
As told in Oliver Green’s Book, The Tube Station to Station on the London Underground, and also shown in the exhibitions and panels at the museum the first underground railway was constructed by the Metropolitan Railway company over the course of three years opening on the 10th January 1863.
Building of the tube
It was built using a technique known as ‘cut and cover’, where a trench was dug and the sides were temporary shored up with timber bracing. Thick walls were then constructed and roofed over with an arch. A two-meter deep layer of topsoil was laid on top and the road above rebuilt.
At the time, some people objected to the idea arguing that the weight of the traffic would collapse the tunnels and that buildings would be shaken to their foundations. They also worried that passengers would be poisoned by the emissions from the trains.
Problems and changes
As it turned out this last fear was in some ways founded, as one of the main problems with these first underground trains was that because they were steam trains there was production of smoke and fumes in an enclosed space. This remained a problem, despite the existence of ventilation shafts in the tunnels, until electric trains were brought in in the 1880’s.
When London became more congested, and ‘cut and cover’ techniques were no longer an option as it was now too expensive and disruptive (several of the buildings listed as demolished structures in London during this time were in fact partially damaged by the construction of the tube) a new method had to be found for making deeper tunnels. Engineer Peter Barlow was responsible for the invention of a cylindrical iron shield which worked “like a giant apple corer”.
Miners would excavate the earth from inside the shield which was forced forward by hydraulic rams. The newly dug section was then lined with iron segments to form the tube tunnel. Luckily, the soft clay that is present under most of London is good for tube tunneling as it is easy to dig out and doesn’t collapse easily. However, there are also unstable sand and gravel beds under London.
The Underground today
Nowadays tunnels under London, such as those built by Crossrail, are excavated using custom made tunnel boring machines (TBMs). Earth pressures balance (EPB) machines are used in soft ground because they maintain a balance between earth and pressure. Slurry Shields (SS) are used when there is high water pressure and large amounts of ground water. They have a sealed, pressurised, air-locked chamber behind the cutter head to hold back the ground water and pipes to remove the wet earth.
From all this it is clear that the Underground has played a major part in our history both in terms of innovation, engineering and simply the way that we get around the place in our daily life. By reducing the numbers of buses and cars in the city centre it has a major impact on London’s CO2 emissions. It was the first of its kind although it was quickly followed by others such as the Budapest Metro. It has even proved to have uses that could never have been previously imagined, for example being used as shelters during air raids in the Second World War.
Both with its important role as one of London’s historic features and as a busy transport system, which is kept up to date for the demands of the 21st Century, the London Underground is definitely something to celebrate!