A rare memento of the Industrial Revolution is set to go on sale next month. The graphic designs for the world's first underwater tunnel, the Thames Tunnel, signed by Sir Marc Isambard Brunel and his son Isambard Kingdom Brunel are headed to auction as part of Bonhams Fine Books, Atlases, Manuscripts and Photographs Sale in London on November 15.

The Thames Tunnel is an unsung historic landmark of London. Though it was one of the great achievements of the heroic age of engineering, thousands of people pass through it daily without being aware of its significance. Tunnels were not a new thing in Victorian Britain – they'd been dug for thousands of years all over the world – but what made the Thames Tunnel different was that it was the first passenger tunnel ever to be constructed under a navigable waterway, and it was built to handle the traffic of what was then the largest city on the planet.

The Thames Tunnel is located in the East End of London, running under the River Thames between Wapping and Rotherhithe. It's 1,300 ft (396 m) long, 35 ft (11 m) wide and 20 ft (6 m) high, and runs under the river bed at a depth of 75 ft (23) from the river surface at high tide. It was built between 1825 and 1843 by Anglo-French engineer Sir Marc Isambard Brunel and his son Isambard Kingdom Brunel, who went on to become one of the greatest engineers of all time.

London in the early decades of the 19th century was booming and the expansion of the capital, especially the docklands along the banks of the Thames, caused a growing need for a river crossing below London Bridge. However, it wasn't possible to use a bridge due to the width of the river and the need to be high enough to let ships pass beneath. The alternative to building up was to dig down.

The Brunels' project wasn't the first attempt. Others had tried and failed since 1799 and the task was thought to be impossible because of the sodden clay that made up the river bottom. That didn't stop Marc Kingdom Brunel from submitting a plan to a group of private investors in 1823 for a tunnel to carry foot traffic and horse-drawn carriages. This proposal would be dug using a revolutionary new boring apparatus – the shield.

When work began in 1825 the first problem was getting deep enough to start the tunnel. The Brunel's began by dropping a large shaft on the south bank at Rotherhithe using an iron ring 50 ft (15 m) in diameter topped by a brick wall 40 ft (12 m) high and 3 ft (91 cm) thick. Pumps run by a steam engine were incorporated into the shaft and as the soil was removed by hand, the apparatus sank under its own weight as it cut through the earth. Later, a second shaft was sunk across the river at Wapping as the exit.

When the Rotherhithe shaft was completed, the tunnel proper was begun using Marc Isambard Brunel's and Thomas Cochrane's newly invented tunneling shield technology, which was patented 1818. This consisted of a huge iron ring open at the back and sealed at the front by 12 huge frames. Each frame was divided into three stages to form 36 cells with a workman in each cell.

The front of each cell was made up of boards. These were removed one at a time, the earth in front was dug out by hand, the board was put back and screwed forward, then the workman went on to the next board. When all the boards were screwed out, the cell itself was moved ahead, then the entire shield was moved using hydraulic jacks pressing on the ring. In this way, the shield advanced, holding up the tunnel while the brickwork was laid and sealed behind.

The work on the Thames Tunnel was much safer and faster than previous methods, but it was still slow, making only 8 to 12 ft a week. Costs were deferred by charging up to 800 visitors a day a shilling a head to tour the works.

Unfortunately, the air was foul at the best of times, but was made worse by the fact that in those days the Thames was literally an open sewer used to flush away effluent from the entire metropolis. This meant methane, hydrogen sulfide, and disease bacteria like cholera were constantly seeping into the tunnel.

There were also disastrous setbacks. On May 18, 1827, a hole opened in the river floor and flooded the tunnel. Isambard Kingdom Brunel, aged only 21 and in charge of the project, lowered a diving bell from a boat to repair the hole at the bottom of the river, throwing bags filled with clay into the breach. After the repairs were completed and the tunnel pumped out, he held a banquet inside it to celebrate ... and to raise more funds.

It flooded again on January 12, 1828, killing six men and almost drowning Isambard Kingdom Brunel. In August, the money ran out and work stopped for seven years. When it resumed in 1835, the shield was so badly corroded that it had to be replaced. Floods and fires continued to hamper work.

But in November 1841, tunneling was completed. The costs came to £454,000 for digging and £180,000 to complete it with gas lights, pumps to keep it dry, roadways and spiral staircases. A vast sum in those days. It opened to the public on 25 March 1843.

The reception of the Thames Tunnel was on the level of the Concorde or the Moon landing. It was hailed in its day as the Eighth Wonder of the World and became a major tourist attraction, though it was only open to pedestrians and not a financial success. It was sold to the East London Railway Company in September 1865 and later became the oldest segment of the London Underground.

Today, it's a Grade II listed monument and part of the London Overground serving Greater London and parts of Hertfordshire. The tunnel has a museum associated with it and conducted tours are available during maintenance periods.

But the significance of the Thames Tunnel goes well beyond another path across the Thames. The techniques used for the tunnel were so advanced that modern mechanized versions of the shield are used to dig tunnel's all over the world on projects including the Channel Tunnel and the recent road tunnel under downtown Seattle.

As to the builders, Marc Kingdom Brunel was lionized in his lifetime and Isambard Kingdom Brunel's career was so successful that he placed second only to Sir Winston Churchill in a 2002 BBC poll to identify the 100 Greatest Britons.

Ironically, Isambard's son, Henry Marc, became an engineer in his own right and was part of the project to build Tower Bridge upstream of the Thames Tunnel – an achievement that made the latter obsolete.

In 1837, Marc Isambard Brunel presented a set of drawings of the shield to the Institute of Civil Engineers and received their Silver Medal. The collection for sale by Bonhams is different. A more comprehensive set, it comes from a signed Brunel family album that belonged to a direct descendant of Marc Isambard Brunel. Not only does it have drawings of the tunnel and the shield, it also includes early design ideas for the tunnel, and rough sketches. In addition, the sale includes a cardboard model of the shield.

"This is an extraordinarily important archive of one of the great engineering feats of the pre-Victorian era – not just in Britain but in the world," says Bonhams Head of Books and Manuscripts, Matthew Haley. "The Thames Tunnel can be seen as Marc Isambard Brunel's last great project, and the launch pad for the meteoric career of his son, Isambard Kingdom Brunel."

The Thames Tunnel collection goes on sale on November 15 at the Bonhams Knightsbridge gallery. The expected price is between £50,000 and £100,000 (US$66,000 to US$130,000).

Source: Bonhams

View gallery - 11 images