Director’s Diary: Atlantic Bridges by Roebling & Brunel

On board Norwegian Cruise Line Epic we arrive in Cadiz: splendid views across the bay of El puente de la Constitución de 1812 or Puente de La Pepa, the new cable stay bridge. This is the work of the controversial Santiago Calatrava and a type of suspension bridge
My last talk ATLANTIC BRIDGES is about suspension bridges built by two brilliant engineering dynasties: Roebling in America and Brunel in Britain. Instructive to remember, especially in our troubled times, that these are two migrant families. Marc Brunel was born 1769 in Normandy, France, and fled the Terror. Pictured with his son Isambard and grandson Henry Marc
Johann August Röbling was born 1806 in Prussia and emigrated to America to take up farming in1831. Pictured with his son Washington and daughter-in-law Emily
I focus on three bridges from each dynasty:
Hungerford Bridge & Clifton Suspension my Egyptian thing’
Blackfriars Railway Bridge
Tower Bridge (iconic London)
Niagara Suspension Bridge
Roebling Bridge (Delaware Aqueduct)
Brooklyn Bridge (iconic New York)
Brunel’s Hungerford Bridge 1841(and Clifton Suspension)
Brunel’s Hungerford Bridge an elegant suspension bridge, with fine towers built in the Italian campanile style. It took pedestrians to Hungerford market, now the site of Charing Cross Station. The bridge was taken down in 1864 to build a railway bridge into the new railway station, but the piers remain. Elegant towers, red brick, white facing and terracotta roofs – like something you might see in Florence. The Hungerford chains now span the Avon Gorge for the Clifton Suspension Bridge, built by engineer Hawkshaw to Brunel’s design after his death and as a tribute to him.
John Roebling’s Niagara Bridge 1855
Roebling’s double-deck bridge has a lower deck for pedestrians and carriages, and an upper deck for trains. Engineers were skeptical. Robert Stephenson said “If your bridge succeeds, mine is a magnificent blunder.” Successfully completed in four years, connecting the two countries by the first working suspension railway bridge in history. Compare Roebling’s limestone towers on each side of the gorge with Brunels towers at Clifton – Egyptian style was much in vogue. In Roeblings bridge, each cable comprised 3,059 wires that were spun with Roebling’s patented technique (used in his Allegheny Suspension Aqueduct).
In the first year of the bridge’s operation, an average of 30 trains crossed
each day. Five years later 45 trains a day. Roebling stipulated that the trains be limited to a maximum speed of 5 miles per hour to ensure absolute safety. He was confident the bridge could handle faster train traffic, but he preferred a safe operation. Three years later in the UK, Brunel built a suspension railway bridge over the River Tamar between Devon and Cornwall: opened 1858, still in use today and with a speed limit of 15 miles an hour…
American Society of Civil Engineers said: “That is the best engineering, not which makes the most splendid, or even the most perfect work, but that which makes a work that answers the purpose well, at the least cost.” Roebling had built a bridge that rivalled grander bridges of leading European nations at a much lower cost, using only one-sixth the material of Stephenson’s Britannia Bridge (half as long) and costing $400,000 (equivalent Stephenson tubular bridge estimated $4 million)
Roebling’s Delaware Aqueduct 1849
also known as the Roebling Bridge 
Oldest existing wire suspension bridge in America, running 535 feet over the Delaware River.  Built because the rope ferry crossing created problems with timber rafts headed downstream. An immediate success, the Delaware Aqueduct cost $41,750 and cut canal travel time by one full day, saving thousands of dollars each year. After the canal closed in 1898, the aqueduct was drained and converted into a road bridge. Eventually, the canal sides and towpaths (walkways for those pulling barges) were removed. It operated as a toll bridge for wagons and, later, motor vehicles until 1979. Designated a National Historic Landmark in 1968.
Brunel would like this improvisatory approach: Thames Tunnel opened not for cargo but for pedestrians, shopping, fairground entertainments and banquets
Brunel’s Blackfriars Railway Bridge 1886
Another Thames bridge, but this one is built by Henry Marc Brunel (son of Isambard Kingdom Brunel) and now next to the red and white Blackfriars Road Bridge. The orange red piers of Cubitt’s original railway bridge still remain, built for the London, Chatham and Dover Railway, but the bridge proved too weak for modern trains, and so was removed. The second Blackfriars Railway Bridge, built in 1886 by Henry Marc Brunel and partner John Wolfe Barry.
Three generations of engineers in the Brunel family: IKB our most famous engineer, little man, big hat, big cigar, big chains, big ideas; his father Sir Marc Brunel, the Frenchman, who some say is the greater genius, and son and grandson, Henry Marc Brunel, who built this bridge. Blackfriars railway station is the first railway station in the world to span a river – you can get on at Blackfriars on the north or the south side of the river, and wait for your train as the river flows beneath you. Also the first solar powered railway station.
Tower Bridge 1894
Built by Henry Marc Brunel and John Wolfe Barry. Architect Horace Jones, who won the design competition, was knighted and dead within a year and before construction had even began. It was built by his engineers, the same team that built Blackfriars Railway Bridge. Tower Bridge is one of the most famous bridges in the world, but the Victorians hated it. They thought it dishonest. The bridge is made of steel, but clad with masonry to fit in aesthetically with the Tower of London. Tower Bridge is the drawbridge for London, but the Victorians thought if you build a steel bridge, it should look like a steel bridge. If you want it to look like a masonry bridge, build it out of masonry.
This was once the busiest river in the world. In Brunel’s day there were three thousand tall masted ships in the river every day. Ten thousand small boats. The river is so busy, they say it takes longer to get stuff across the Thames than it takes to get stuff across the Atlantic. This is the biggest traffic jam in the world. And they need to get stuff across the river as well as up and down it. You can’t build an ordinary bridge, that would stop the tall ships going upstream. But Tower Bridge opens to let the tall masts through. This is another solution to the same problem the Thames Tunnel solved. This is a bascule bridge. Bascule is the French word for see-saw, and those roadways are bascules or see-saws. It’s a see-saw bridge. If you have never seen the bascules go up, visit Tower Bridge website, click on ‘bridge lifts’, they are all scheduled. It costs nothing to have the bridge lift: for hundreds of years, London merchants have bequeathed money for the building and upkeep of the bridges of London. You have to have a ship, mind. They take a dim view of people phoning up to raise it just so they can watch…
Even today, the bridge goes up and down a thousand times a year, on average three times a day. But the bascules are so cleverly counter-weighted, they go up and down in 5 minutes. Each bascule weighs a thousand tons: a thousand tons a thousand times a year.
Each side of the bascules, you see a suspension bridges and with chains in two different configurations to deal with heavy loadings at each end. The first Brunel bridge was a suspension bridge, now Hungerford Railway Bridge, a beam bridge between brick piers. The second bridge, Blackfriars Railway Bridge, is an arch bridge. The third bridge, Tower Bridge, is a bascule bridge with suspension bridges each side. You pass under Tower Bridge from the upper pool to the lower pool. 
Brooklyn Bridge 1883
John Roebling started work on the Brooklyn Bridge in 1866 but died in 1869 following an accident. His son Washington Roebling immediately took charge but developed decompression sickness, known at the time as “caisson disease” which affected him so badly that he became bed-ridden. His wife Emily Warren Roebling stepped in as the “first woman field engineer” and saw out the completion of the Brooklyn Bridge.
Emily took over much of the chief engineer’s duties, including day-to-day supervision and project management. Emily and her husband jointly planned the bridge’s continued construction, she dealt with politicians, competing engineers, and all those associated with the work on the bridge. At the opening ceremony, Emily was honoured in a speech by Abram Stevens Hewitt who said at the bridge was
…an everlasting monument to the sacrificing devotion of a woman and of her capacity for that higher education from which she has been too long disbarred.
Today the Brooklyn Bridge is marked with a plaque dedicated to the memory of Emily, her husband Washington Roebling, and her father-in-law John A. Roebling.
Brooklyn Bridge, iconic New York, was built by a woman.
My last bridge, the Bridge of Arta, is in Greece and also in folklore. Three brothers are building a bridge, but each time the river sweeps the pier away. To ensure success, they agree to sacrifice the first living thing they see. Each of their wives brings them lunch every day, and the one who arrives first is the wife of Manoli, the youngest brother.  In the same way, Agamemnon reluctantly sacrifices his beloved daughter (as instructed by the oracle) to ensure victory over Troy. These deals always end badly. The brothers build the foundations and pier around Manolis wife, and in a gesture showing great humanity, leave a gap so that she can feed her infant baby. The bridge stands to this day, and there is a salt deposit runs from a gap in the pier, just as the mothers milk did. Today, mothers whose babies will not take the breast are feed milk mixed with salt collected from the bridge and this seems to do the trick…
It has been well understood for some time that if you need to sacrifice something, women are best. The bridge in Arta took just one woman; in Brooklyn – where they understood less – they had to sacrifice two men. But Emily Roebling is the engineer who finished Brooklyn Bridge, which suggests they are good at engineering as well as being sacrificed… 
This week in London, heritage boat tours and river walks every day, and visits from Bellenden Primary School (meeting Brunel in Person) and from Thames Tideway Tunnel. Goldsmith College present an Art/Music installation entitled State of Mind on Wednesday; Secret Adventures in Cinema on Thursday; Midnight Apothecary Friday and Saturday. The calendar for the week is below.
Sunday 22nd April
No London Walks, Museum open all day
Monday 23rdApril
10.40 riverside walk from Bermondsey tube offered in partnership with London Walks
Tuesday 24thApril
10.40 riverside walk from Bermondsey tube offered in partnership with London Walks 
Wednesday 25thApril
10.40 heritage boat trip from Embankment tube offered in partnership with London Walks
11.00 Bellenden Primary School meet Brunel in Person
18.00 Thames Tideway Tunnel visit
18.15 riverside walk from Bermondsey tube offered in partnership with London Walks
19.30 State of Mind: Art installation/performance Goldsmith University
Thursday 26thApril
10.40 heritage boat trip from Embankment tube offered in partnership with London Walks
18.00 Secret Adventures in Film, Grand Entrance Hall with cocktails in roof garden
Friday 27th April
10.40 heritage boat trip from Embankment tube offered in partnership with London Walks
17.00 Midnight Apothecary
Saturday 28thApril
10.40 heritage boat trip from Embankment tube offered in partnership with London Walks
17.00 Midnight Apothecary