Sir Christopher Wren traced out the dome of his planned masterwork on the ground and stood at the centre. He had cleared the site of Old St Paul's, ruined in the Great Fire of London of 1666, but not yet started on the new cathedral.
Needing a marker for the centre spot, he called for a labourer to bring him a stone from the rubble scattered around the site. The nearest man brought him the nearest piece of broken masonry. When Wren turned the stone over, he found an inscription with a single word, 'RESURGAM', Latin for 'I will rise again'.
In the pediment on the south side of St Paul's Cathedral, you can see a stone relief carving of a phoenix, its wings outstretched, rising from flames. Below the phoenix is inscribed a single Latin word, 'RESURGAM'.
Fires have played a regular role in the history of St Paul's. The first, built in 604 (of wood), burnt down in 675; the second was destroyed by Vikings in 962 and the third fell victim to a fire in 1087 that destroyed much of Norman London.
The gothic cathedral known today as Old St Paul's and destroyed in 1666, was probably the fourth cathedral on the site. Its construction started under the Normans in 1087 at the beginning of the reign of William Rufus, successor to William the Conqueror. It was consecrated in 1240 and enlarged between 1256 and 1314.
Old St Paul's was 586ft (179m) long and 290ft (88m) wide across the transepts. Its spire was one of the tallest in Europe, second only to Lincoln Cathedral.
Traditionally recorded as 489ft (149m) tall, the spire of Old St Paul's was destroyed in a fire in 1561, which also melted the cathedral's bells and lead roof. Wren later estimated that the spire was a little shorter, 460 feet (140m), but this was still 95ft taller than Wren's own building, which is 365ft (111m) high.
The 1561 fire was probably the result of a lightning strike, but some stories suggest that a plumber left a pan of hot coals in the tower when he went on his lunch break. Either way, the spire was never rebuilt.
By William Shakespeare's day, the late 1500s and early 1600s, the nave of the cathedral was very different from the peaceful place it is today. Known as Paul's Walk, it was used as a marketplace and meeting area. A centre of news and gossip, it thronged with people and attracted beggars, thieves and prostitutes.
By the early 1600s, Old St Paul's was in a poor condition and architect Inigo Jones carried out some restoration work from 1621. He added a classical portico to the West Front in the 1630s, splendid in appearance but oddly out of keeping with the Gothic style of the rest of the building.
During the English Civil War in the 1640s, the restoration work stopped and St Paul's suffered further decline. It was even used as a stable for Parliamentarian cavalry horses.
In 1663, after the restoration of the monarchy, King Charles II established a Royal Commission to consider options for improving or rebuilding the cathedral. This led to Wren's involvement, although he was principally an astronomer and mathematician.
In the days when the profession of architect did not yet exist, Wren's intellectual prowess and scientific mind brought him to the attention of the king and the cathedral's commissioners.
He was also well connected.
His father was a clergyman (also named Christopher) who had been appointed Dean of Windsor when the king's father, Charles I, was on the throne. Wren spent much of his childhood in Windsor Castle, where it is quite possible that he met the future King Charles II when he was still a young prince. Wren's uncle, previously Dean of Windsor, became Bishop of Ely, while one of his cousins went on to be secretary to the Duke of York (brother of Charles II, later King James II).
Wren was educated at Oxford University, where he mixed with a number of eminent scientists, including Robert Boyle (known for Boyle's law) and Robert Hooke, one of the greatest scientists of his generation. A brilliant mathematician, Wren was a capable draughtsman and accomplished maker of models and scientific instruments. In 1657, at the age of 25, he became Professor of Astronomy at Gresham College in the City of London.
During the Civil War and the period of the Protectorate, when Oliver Cromwell and his son Richard ruled in England, the Wren family's royal connections meant that they had to keep a low profile. However, once the monarchy was restored, Wren was able to seize an opportunity arising from an incident from his childhood.
Christopher Wren the Elder, as Dean of Windsor, had managed to save the record books of the Order of the Garter when Parliamentary forces occupied Windsor Castle. Only weeks after the restoration of the monarchy in 1660, Wren sought an audience with King Charles II to return the Garter records that his father had hidden. Perhaps Charles remembered Christopher from their days as boys at Windsor.
The following year, in 1661, Wren was appointed Savilian Professor in Astronomy at Oxford, a very prestigious post, but his scientific interests and achievements were not limited to astronomy.
He also pioneered intravenous injections, invented a range of devices and instruments, carried out experiments in printmaking and was commissioned by the Crown to construct a giant globe of the moon. Wren and his great friend Robert Hooke first came up with the suggestion that the force of gravity followed an inverse square law, although it was Isaac Newton who established the proof.
By 1665, Wren had become increasingly interested in buildings and their design and had taken on a number of architectural projects in Oxford and Cambridge.
In May 1666, at the request of the St Paul's commissioners, Wren produced a report proposing the demolition of the cathedral's tower, which was in a precarious state. His proposed design included a dome. The commissioners were divided between those in favour of repairing the existing tower and those supporting demolition and rebuilding.
A meeting on 27 August 1666, at which Wren and the great diarist John Evelyn were present, accepted Wren's view, but only after much discussion.
Less than a week later, in the early hours of Sunday 2 September 1666, a fire started in Thomas Farriner's bakery in Pudding Lane, around half a mile east of St Paul's. By 6 September the cathedral and most of the City of London had been destroyed.
The fire had reached Old St Paul's in the evening on Tuesday 4 September. It quickly spread from the surrounding houses to the wooden scaffolding around the tower of the cathedral, which had been erected for restoration work.
The flames were further fuelled by books, pamphlets and papers that had been placed in the crypt. The printers and booksellers that used to trade in St Paul's Churchyard had placed their inventory in what they assumed was a fireproof space before fleeing.
The heat of the fire that consumed St Paul's was so intense that stones flew like grenades and the lead from the roof melted and flowed down the streets.
The fire left the greater part of the walls of the cathedral standing, albeit with their stained glass windows destroyed. However, the roof and part of the crypt's vaults were destroyed. Inigo Jones' portico was damaged beyond repair and the tower was in a dangerous state.
After some early plans to patch up the old fabric of the building, it soon became apparent that it was unsafe. Wren's preferred solution of tearing it down and building a new cathedral was adopted.
The demolition work began in earnest in 1668, including the use of battering rams and even gunpowder, and continued until the mid 1680s (after construction of the new cathedral began).
Wren developed a number of designs for the new building from 1669. King Charles II approved a domed 'Greek Cross' design in 1672 and a wooden model was completed in 1674. The Great Model, 13ft (4m) high and almost 21ft (6.4m) long, is still on display in the cathedral today.
However, the model attracted criticism. The clergy considered the design not sufficiently Cathedral-like and there were also concerns that the design could not be built in phases. For financial and practical reasons, it was important to be able to complete and open parts of the cathedral in stages, rather than wait until it was all complete.
Wren worked up more ideas, and the so-called Warrant design (because it was approved by royal warrant) was approved in 1675. It was the basis for construction to start, but the Warrant design differed from the cathedral we see today a number of details.
The most significant differences include the following:
the Warrant design had no screen walls above the aisles (so buttresses supporting the roof would have been visible),
the towers at the west end were different,
the west portico was similar to Inigo Jones' classical design for Old St Paul's, and
the Warrant design had a very different dome concept, including a spire on top of a dome.
Wren took advantage of the leeway that was allowed to him to make changes to the design as construction proceeded, ending up with something closer to the Great Model than the Warrant Design envisaged.
The first stone of the new cathedral was laid in June 1675. Construction started with the choir at the east end and gradually moved westward.
The first service to be held in the partially completed cathedral was on 2 December 1697, before the dome had even had its design finished, let alone been built. Slow progress with the project led Parliament in 1697 to withhold half of Wren's salary until completion of the works.
At this point, Wren made it his priority to complete the dome, which was to be the largest in England and the second largest in the world after St Peter's in Rome. The only other domes ever built in England at that time were also by Wren in other post-fire City churches (St Stephen Walbrook and St Mary Abchurch).
The dome of St Paul's was designed with significant input from Robert Hooke, who contributed great scientific insight of the age. It also benefited from draughtsmanship by Nicholas Hawksmoor, then a junior assistant to Wren and later an eminent architect in his own right. Large stone models were built to test the design, a vital step at a time when mathematics was not yet advanced enough to predict its safety with certainty.
The final design is often described as three domes, but is really two domes and a cone. The outer dome, covered with a lead skin, is supported by a wooden frame, itself built around an inner brick cone with a domed end to it. The brick cone also supports the lantern that appears to sit on top of the outer dome. Within the cone, there is an inner dome visible from inside the cathedral, with paintings by Sir James Thornhill.
Parliament declared the cathedral officially complete on 25 December 1711 (when Wren was paid), although some work continued for some years afterwards. Thornhill's inner dome paintings (which Wren opposed) were completed in 1721 and statues for the west pediment by Francis Bird were finished a year later.
The accounts of the construction record that by 1716, it had cost £804,758. It was paid for partly through donations and partly through London's Coal Tax, which was increased after the Great Fire to help fund reconstruction in the City.
The 90 year old Sir Christopher Wren died on 25 February 1723. In addition to St Paul's Cathedral, his masterpiece, he also supervised the post fire design and building of 51 churches in the City of London and the Monument to the Great Fire (together with Robert Hooke). Other works outside the City include the Royal Hospital Chelsea, the Old Royal Naval College Greenwich.
Wren was buried in the crypt of St Paul's. An inscription on the wall above his tomb reads 'LECTOR, SI MONUMENTUM REQUIRIS, CIRCUMSPICE' ('Reader, if you seek a monument, look around you').
Like the mythical Phoenix, St Paul's rose again from the flames of the Great Fire, in accordance with the inscription on Wren's stone marker. This is his monument.
St Paul's photo gallery
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