Thomas Farnolls Pritchard: The Shrewsbury Architect Behind the Iron Bridge

Who was Thomas Farnolls Pritchard?

Thomas Farnolls Pritchard (sometimes written Farnolls Pritchard) was born in Shrewsbury in May 1723 and baptised at St Julian’s Church on 11 May.^[1] He is best known for designing the Iron Bridge, the first major bridge in the world made of cast iron.^[2][1] That hides a career that was mostly about chimney-pieces, interiors and church monuments.^[1]

His father was a joiner, and Pritchard trained as a joiner too, before becoming an architect and interior designer.^[1] Other sources describe his training differently: Parks & Gardens UK says he was originally a joiner and that his early training is not well documented,^[3] Shrewsbury Local History says his father was a carpenter,^[4] and English Heritage says he trained as an architect and stonemason.^[5] That background matters for the story of the bridge. A joiner thinks in joints, and the Iron Bridge is famous for iron that was cast to look like carpentry. This article tells his life, lists the works that are attributed to him, explains his role in the bridge, and shows where in Shrewsbury and the Marches you can see his work.

For the wider setting see our guide to Georgian Shrewsbury and the overview of Shropshire’s architectural heritage.

A life in dates

The outline of his life, from Wikipedia, English Heritage and the Ironbridge Gorge Museum’s history of the bridge (citations are in the table):

Shrewsbury Local History adds dated detail: in 1747 he adapted Broom Hall for the newly created Salop Infirmary, in 1749 he took charge of rebuilding St Julian’s and kept the medieval tower, in 1761 he designed Swan Hill Court House, and in 1774 he designed and built a bridge at Stourport.^[4] It dates the Foundling Hospital to 1765 where Wikipedia says 1760 (the table follows Wikipedia), and says his Drawing Book was found in Washington DC in 1964.^[4] Sources also differ on his dates: Parks & Gardens UK gives the death as 23 December 1777 in its text but 22 December in its details panel, and gives conflicting baptism and birth dates,^[3] while the Ironbridge Gorge Museum’s characters page says he died in 1778, the year before the bridge was finished.^[8] For the date of death we use 23 December 1777, the date given by Wikipedia and consistent with English Heritage’s statement that he died a month after work began in November 1777.^[1][7]

What a Georgian architect and joiner actually did

As general background, in the 18th century the line between architect, builder, carpenter and decorator was blurred. Pritchard’s specialities were chimney-pieces, interior decoration and funerary monuments, and his early monuments were Rococo or Gothic in style while his later work was neoclassical.^[1]

The works attributed to him include:

• Shrewsbury: the rebuilding of St Julian’s Church; the Foundling Hospital (built 1760, later a workhouse and adapted for Shrewsbury School in 1882); 6 Quarry Place^[9]; and monuments in St Mary’s.^[1]
• Ludlow: a rebuilt jail, work on the Hosier’s Almshouses and alterations to the Guildhall.^[1]
• Interiors: Croft Castle and Gaines in Herefordshire, Shipton Hall, and the ballroom at Powis Castle.^[1]
• Chimney-pieces: at Broseley Hall, The Lawns and Benthall Hall.^[1]
• Monuments: to Ann Wilkinson (1756, Wrexham), the Rev. John Lloyd (1758) and Mary Morhall (1765) in St Mary’s, Shrewsbury, Richard Corbet at Moreton Corbet, and others at Acton Round, Ludford and Barrow.^[1]

Joseph Bromfield, who started as a plasterer, took over much of Pritchard’s practice after his death,^[1] and the Crescent on Town Walls (1793) is one of Bromfield’s works.^[9] William Baker of Audlem used Pritchard’s plans for St John’s Church in Wolverhampton.^[1]

Pritchard's Shrewsbury: a short trail

Not every attributed building is open to visit, but several can be seen from the street. St Julian’s Church, where he was baptised and buried,^[1] is in the town centre. 6 Quarry Place, a later 18th-century town house, was built for the Rev. Richard de Courcy, vicar of St Alkmund’s, and designed by Pritchard according to the Shrewsbury Civic Society,^[9] which says it was later a nursing home and, in the First World War, an officers’ hospital. Monuments in St Mary’s Church are best seen when the church is open, so check access first.

The Iron Bridge: the idea

The Iron Bridge crosses the River Severn at what is now the town of Ironbridge. In 1773 Pritchard wrote to John Wilkinson, the ironmaster, suggesting that the bridge be built in iron, and his 1775 design proposed a single arch so that the bridge would not obstruct boats on the river.^[6] English Heritage adds that his designs were approved by Act of Parliament and that construction began in 1777.^[7] A group of local businessmen commissioned Abraham Darby III to build it, partly to showcase cast iron and the skills of the Coalbrookdale Company.^[6]

The first Abraham Darby (1678-1717) pioneered smelting iron with coke from local coal at Coalbrookdale in 1709, which made mass production of cast iron economically viable. His grandson, Abraham Darby III, took over the project after Pritchard’s death and cast the iron at his Coalbrookdale furnaces.^[7] The Ironbridge Gorge Museum says Darby acquired the Bedlam Furnace in 1776 and that it cast much of the iron used in the bridge.^[8] English Heritage says he paid £3,000 towards the cost.^[5]

How the bridge was built

Work began in November 1777 and the bridge is described as built in 1779;^[6] it opened to traffic on New Year’s Day 1781.^[7] Darby estimated the cost at £3,200 and the final cost was about £6,000.^[6][7] English Heritage gives the iron used as 378 tons, or almost 400 tons,^[7] and the Ironbridge Gorge Museum says about 384 tonnes would have been needed;^[6] the sources differ slightly. The span is about 30 metres,^[2] which English Heritage gives as 100 feet, with a weight of 378 tonnes.^[5] The Ironbridge Gorge Museum dates the plans to 1773, the start of construction to 1777 and completion to 1779.^[8]

One of the details that makes it special is that the ironwork copies carpentry. The joints are dovetails and mortise-and-tenon joints, the kind a joiner would cut in timber, executed in cast iron.^[2] It is tempting to see the hand of a joiner-architect here, but be careful: the sources describe what the joints are, not who chose them, so treat the connection as an attractive possibility, not a proven fact.

For over 200 years it was unclear exactly how Darby erected the bridge, because few images or eyewitness accounts survived. Darby’s accounts suggest scaffolding, timber and rope were used, and a watercolour sketch by Elias Martin, found in Stockholm in 1997, appears to show a wooden framework used to raise the half-ribs from a vessel’s deck.^[7]

Did Pritchard design the Iron Bridge? A careful answer

Short answer: Pritchard proposed it and designed it; Darby built it. Longer answer: the Ironbridge Gorge Museum attributes the 1775 design to Pritchard and the construction to Darby, and English Heritage says Pritchard proposed the bridge in 1773 and that his designs were approved.^[6][7] What the sources do not tell us in detail is how much the design changed between 1775 and the finished bridge, or how much Darby and his workforce altered it. Because Pritchard died a month after construction began, he did not oversee the build.^[7] Shrewsbury Local History says he produced early designs with Darby and John Wilkinson and that the final bridge is essentially his design.^[4] Parks & Gardens UK says he designed and built the bridge, but gives no source, so we do not rely on it for the building.^[3] When someone says “Darby’s bridge”, they are describing who made it. When they say “Pritchard’s bridge”, they are describing who first drew it.

Cast iron explained: why the bridge is an arch

Cast iron is iron poured into a mould. It is very strong when it is squashed (in compression) and weak when it is stretched (in tension), which is why an arch is the right shape for it: an arch turns the loads into compression. Abraham Darby I’s coke-smelting at Coalbrookdale in 1709 made mass production of cast iron economically viable,^[7] and his grandson Abraham Darby III cast the iron for the bridge at his Coalbrookdale furnaces.^[7] Cast iron is different from wrought iron, the tougher bar iron (a general point, not drawn from the sources above).

Terms used in this article

Common misunderstandings

• “Abraham Darby designed it.” Darby built it. The Darby who pioneered coke smelting was Abraham Darby I (1678-1717); the bridge was built by his grandson, Abraham Darby III.^[7]
• “It was the first iron bridge.” It was the first major bridge in the world made of cast iron and the first cast-iron arch bridge.^[2][1]
• “Pritchard saw it finished.” He died in December 1777, a month after work began.^[7]
• “The final cost matched the estimate.” It did not: Darby estimated £3,200 and the final cost was about £6,000.^[6]

After the bridge

The bridge survived a major flood in 1795. It was closed to vehicles and designated an Ancient Monument in 1934, became a UNESCO World Heritage Site in 1986 (as part of the Ironbridge Gorge), and is now a Scheduled Monument and Grade I listed.^[2] A major conservation project finished in 2018.^[7]

Today the bridge, not the chimney-pieces, is how he is remembered, but chimney-pieces and interiors were his specialities, and that decorative tradition is the one our own work belongs to. Our history of the ceiling rose explains how the form developed in these decades, and our Georgian interiors guide shows what a room of this period looked like.

Visiting

The Iron Bridge is at Ironbridge, in the Ironbridge Gorge, a short drive from Shrewsbury. English Heritage publishes visitor information and a history of the bridge.^[7] As access, parking charges and opening arrangements change, check the current English Heritage and Ironbridge Gorge Museums pages before travelling. If you want to see interiors he worked on, check current access to Powis Castle and Croft Castle before you go.

If you like the Georgian details, a handmade plaster ceiling rose is a way of bringing them home, and our guide to Robert Adam shows the style that replaced Pritchard’s Rococo.

Keep reading

• Georgian Shrewsbury: streets, townhouses and details
• Shrewsbury Flaxmill Maltings: the first iron-framed building
• History of the ceiling rose
• Georgian interiors guide
• Plasterwork houses to visit in the UK

Shop the look

Duchess Ceiling RoseAcanthus Overdoor Pediment — 35 inLuna Japandi Wall Light

Frequently asked questions

Who designed the Iron Bridge?

Thomas Farnolls Pritchard, a Shrewsbury architect, proposed the bridge in 1773 and drew up the 1775 single-arch design. Abraham Darby III built it, casting the iron at Coalbrookdale. Pritchard died in December 1777, before it was finished.

When was Thomas Farnolls Pritchard born and when did he die?

He was born in Shrewsbury in May 1723 (baptised on 11 May at St Julian's) and died on 23 December 1777, aged 54. He was buried at St Julian's, Shrewsbury.

When did the Iron Bridge open?

Construction began in November 1777, the bridge is dated to 1779, and it opened on New Year's Day 1781.

How much did the Iron Bridge cost?

Abraham Darby III estimated £3,200. The final cost was about £6,000.

Why does the Iron Bridge look like carpentry?

The ironwork copies carpentry joints such as dovetails and mortise-and-tenon joints. Pritchard was trained as a joiner, though the sources do not say who chose the joints.

What else did Pritchard design?

He worked on St Julian's Church and a Foundling Hospital in Shrewsbury, 6 Quarry Place, the jail and Guildhall in Ludlow, and interiors at Croft Castle and Powis Castle, as well as chimney-pieces and church monuments.

Was Pritchard an architect or a carpenter?

Both. His father was a joiner and he trained as a joiner before becoming an architect and interior designer, specialising in chimney-pieces, interiors and monuments.

Who took over Pritchard's practice?

Joseph Bromfield, originally a plasterer, took over much of it after Pritchard's death. Bromfield built the Crescent on Town Walls in Shrewsbury in 1793.