Thomas Telford in detail (3)

Thomas Telford in detail (3)

This is the third part of the feature on Thomas Telford’s achievements. The first part of this feature used colour versions of the Rosoman painting located on the left hand side of the work sourced from the Internet with some upscaling involved. Th post depicts the structures on the right hand side of Leonard Rosoman’s 1957 art work – however one part of it is at least a hi-res black and white pic scanned from my Telford Bicentenary book. There’s unfortunately no examples of the right hand side with sufficient hi-res rendering to do it in colour.

As mentioned earlier in this series, the highlighted structures that were marked as some of Telford’s finest on Leonard Rosoman’s painting of 1957 are numbered thus readers can relate those with the features depicted below. In the first post the left hand side of the image (numbers one to five) were discussed, whilst in this second post its the right hand side (numbers six to eleven.)

The Telford Bicentenary Painting being worked on by Leonard Rosoman and an assistant. July 1957. The numbers on this picture correspond to the various subjects detailed below in this post. Source: University of Nottingham. (Note: The file from which the screencap above originates has now been deleted however its original source is shown below.)

Starting off with number six on the Rosoman painting, this is clearly a three arched bridge, however I have no clue which one it is. Telford built a number of three arched bridges thus it could be any of those. One thing is certain, the top half of the painting clearly references Telford’s monuments in Scotland, thus we know the bridge is in that country but which is it? There’s a tower next to the bridge and I thought this might reference the Kildonan monument in Sutherland, thus the mystery bridge in question should be that at Helmsdale. The only problem is Helmsdale bridge has two arches, not three, so that’s left me stumped as to where it could be.

I must add a ‘6a’ to the painting because there is in fact a castle depicted on it! It hasn’t been numbered however because, for one thing, Telford was never its designer or engineer! Its Edinburgh Castle. To some it might look like a clump of trees atop a hill however. The picture does apparently show the famous castle because there’s a rocky outcrop below the castle itself and that is how it is in real life. Not only that the peaked summit just behind the castle is in my view, but the area also just outside Edinburgh known as Arthur’s Seat.

A rough depiction of Edinburgh Castle can be seen in the centre of this crop from the painting.

There’s also a 6b in fact. Its another castle on the extreme left side of the cropped picture shown here. Its another castle but so far I have been unable to find out where that could be. And a 6c too in fact! This is the mysterious tower. Telford didnt build the Kildonan monument so I don’t know what it could be. This and the others will simply have to remain a mystery unless someone could possibly tell me what they are. Anyway numbers 7 and 8 are next….

7) Glencorse Dam

Curiously there seems to be a dam that is depicted and that is number seven on the painting. Did Telford build dams? Not generally but there is one example that he was involved (in collaboration with James Jardine) this is Glencorse Reservoir in the Pentland Hills to the south west of Edinburgh. This was built as a water supply for Edinburgh and the image depicted by Rosoman clearly represents the dam at the head of Glencorse Reservoir. Finding pictures of this proved to be difficult however that shown below should be sufficient enough…

Glencorse Reservoir showing the earthen dam towards the bottom. Source: Twitter

8) Craigellachie bridge

Another of Telford’s bridges depicted is numbered eight on the index painting. Its the cast iron bridge at Craigellachie. This is about twelve miles south of Elgin in the north of Scotland. It opened in 1814 and is noted for having a slender cast iron structure that spans a huge length across the River Spey. The cast iron is unusual because it is highly tensile, meaning it is very strong. It had to be like that because the bridge isn’t a fully self supporting structure as parts of it are not under compression. Each end of the bridge is marked with a pair of castellated towers.

Nice aerial view of Craigellachie bridge. Source: Twitter

Lovely shot of Craigellachie bridge. I chose this picture out of many because it shows the castellated towers and the plaque that tells us it was cast at Plas Kynaston. its the same ironworks that supplied the cast iron for many of Telford’s other projects, including Menai and Pontcysyllte. Source: Twitter

The plaque that can be seen at the side of the road. Source: Twitter

Neptune’s staircase can be seen on the right side of this crop of the Rosoman painting. Craigellachie bridge is shown at the bottom whilst Glencorse Reservoir is depicted at the top.

9) Fort Augustus – Banavie locks/Neptune’s Staircase

Good old Neptune himself (or rather his namesake) comes next for the eight locks on the Caledonian Canal. The locks’ official name is the Banavie flight, but its better known as Neptune’s staircase. Its the largest of the lock flights which lift the Caldeonian Canal up to the Great Glen.

Neptune welcomes you! Source: Twitter

Neptune’s staircase, so called because it is a continuous flight of locks all joined together. Its the longest in the UK. There’s the Foxton locks in Leicestershire which has ten – however these are divided into two groups of five locks thus doesn’t come anywhere near the eight seen at Banavie. The locks were designed by Thomas Telford and built between 1803 and 1811. The canal itself was finished in 1822, its slow progress being somewhat due to shortage of labour.

The Jacobite steam train, hauled by Black Five 45407 ‘The Lancashire Fusilier’ seen in 2017 en route to Malliag, crossing the swing bridge at the foot of Neptune’s staircase. Source: Twitter

Details of the Jacobite steam trips can be found here if anyone is interested. Those for 2021 should recommence from late April onward.

Dramatic view of Neptune’s staircase. The Fort William-Mailiag railway swing bridge is prominently seen. Quite a few sources suggest the bridge was built by Telford too. There’s one problem with that – the railway didn’t exist until the end of the 19th century when its construction began. Source: Twitter

Aerial view of the locks. Part of Ben Nevis can be seen on the left. Fort William is to the right. The body of water in the distance is Loch Linnhe (with Loch Eil to the right) which heads out towards the sea. Source: Twitter

Neptune’s staircase and Ben Nevis, Britain’s highest mountain. Source: Twitter

Telford’s famous aqueducts

The aqueducts at Pontcysyllte and Chirk (Y Waun) are some of Telford’s most celebrated works. They’re not the only aqueducts he bult however for there are others too, just not on such a grand scale though.

Telford’s famous canal aqueducts as depicted on the Rosoman painting.

10) Pontcysyllte Aqueduct

Portrait of Thomas Telford with his famous aqueduct depicted as a background. Source: Twitter

Numbered ten is the stupendous Pontcysyllte aqueduct, sometimes nicknamed ‘The Stream in the Sky.’ in reference to its vast height. The building of this stupendous structure was a departure for Telford (and engineering in particular.) It was initially seen as a crazy idea because no-one had to that date built a crossing that would be so high and so long whilst construction techniques were simply not up to the task at the time.

It was in fact several others besides Telford who came up with the ingenious solutions in order to overcome those engineering limitations, and one of those was to use hollow piers. That wasn’t a cost saving exercise but rather an ingenious solution in terms of the weight factor in having stone piers that were exceedingly tall. The whole structure at its tallest was over a hundred and twenty six feet (38.4m) in height above the River Dee. Up until then no-one had managed to build piers no more than perhaps thirty feet in height!

Lovely period view of the Vale of Llangollen, showing Pontcysyllte aqueduct with Trevor Rocks and Castell Dinas Bran by George Fennel Robson. Source: Twitter

Another problem was how to build the whole structure. The equivalent of building the aqueduct today is akin to building a tall skyscraper and yet in those days (1797-1805) they didn’t have tall cranes or scaffolding or lifts or any sort of powered machinery that would help in its construction. The construction of the aqueduct took a lot of ingenuity and planning. Telford himself was at times stuck for answers and he too had to consult others in an attempt to find solutions. The work of building the aqueduct was overseen by William Jessop, another notable and more experienced civil engineer, whilst the design itself was enhanced by input from William Hazeldine and William Turner (who had drawn up the initial proposals for aqueducts at both Chirk and Pontcysyllte in 1792.)

Aerial view showing the full extent of the aqueduct. View looks west. Source: Twitter

The aqueduct originally had a greater purpose intended for it than that seen today. In fact it seems somewhat a huge structure for what is essentially such an insignificant waterway. The Llangollen canal wasn’t expected any sort of major canal – not like it is these days (and that is because the aqueduct alone is a huge attraction.) The original plans were for a substantial canal route from Shrewsbury to Chester, however the money for that ran out and just part of the route, including the Pontcysyllte aqueduct, was built from a point to the south of Ellesmere to a point just north of the aqueduct. In due course this section of unfinished waterway was connected up to the Ellesmere Canal (which in turn connected up to the Birmingham and Liverpool canal.)

To ensure a supply of water for the newly connected waterways a feeder canal was built from the north end of the aqueduct to Llangollen and beyond there to Berwyn (aka the Horseshoe Falls.) It wasn’t intended to be some wow factor canal but merely a small navigable feeder that would bring water from the River Dee in order to supply the canals. Thus the Llangollen canal is essentially different bits of waterway cobbled together in order to make up a continuous route. In due consideration of its important water source it eventually became a water supply too for most of Cheshire and that alone ensured the canal’s (and the aqueducts) survival.

**Pontcysyllte aqueduct has a particular affection for me as I worked on the trip boats which ventured over it. This was around forty yeas ago – in fact I wrote two articles about the aqueduct for a magazine at the time. The much longer trips from Trevor (on the north side of the famous aqueduct) included Chirk aqueduct.

11) Chirk Aqueduct

The final entry, eleven, is Chirk aqueduct. One of the surprises I find with Leonard Henry Rosoman’s painting is how Telford’s famous canal aqueducts have been represented. Of course its to do with scale and trying to fit both these into Rosoman’s imaginary landscape, but in a conventional sense Chirk and Poncysyllte aqueducts should be the other way round as it somewhat appears Pontcysyllte is relegated to second place, when in fact its one of Telford’s most stupendous achievements.

Its a fantastic structure even if its not quite as massive as that further along the canal at Pontcysyllte. Chirk aqueduct’s setting is stupendous especially when its seen from the valley framed by the narrow Cieriog valley. At Pontcysyllte the hills are quite far apart however at Chirk they are very close and that gives this aqueduct a stronger dramatic background its bigger relations doesn’t have.

Rosoman seems to have had little option to represent these two aqueducts any other way except how it has been done in his painting. Chirk aqueduct is more of a classical structure really, it was a more straightforward job for Thomas Telford, its not some super advanced construction that took engineering to the absolute limits that were possible at the time (this being the very late eighteenth/early nineteenth century.) The only nod Telford made in lieu of modernity is Chirk aqueduct contains a cast iron channel for the canal.

Chirk aqueduct as it is these days. This picture is history in fact for it shows a Wrexham & Shropshire train on the adjacent viaduct en route to London. This quite promising independent rail operator ran for three years before giving up in view of the low patronage attracted. Source: Twitter

Cleaning and repairing the cast iron channel within Chirk aqueduct in 1954. Source: Twitter.

Dramatic view of both aqueduct and railway viaduct. Source: Twitter (Note: The tweet is no longer available thus an archived image is used here.)

Thomas Telford in detail posts:

Thomas Telford in detail 1

Thomas Telford in detail 2

Thomas Telford in detail 3