It was an industry which helped build the nation - but while its legacy can be seen from pub and street names, there is a danger Kent's rich history of brickmaking may disappear under the very earth from which it sprang.

At its peak in the 19th century, it was supporting thousands of jobs and helping fuel the industrial landscape.

Victorian London was built - in part at least - off the back of the toil of those in our county.

But competition and the First World War would see brickworks fade and disappear from our landscapes - leaving only clues as to where many were once sited.

"Brickfields were everywhere," explains David Cufley, a retired structural engineer, member of the British Brick Society, and president of the North West Kent Family History Society.

"I jokingly used to say when I gave talks that there was a brickfield within a brick's throw of here - and that's virtually true.

"There were hundreds of them around."

And it's no exaggeration to say that thousands of homes now stand on what were industries connected to the trade.

Such has been the transformation of the sites, historians say they now struggle to identify areas which once provided one of the county's economic backbones.

Brickfields first started to emerged following the Napoleonic wars in the early 1800s as Britain's wealth and power generated growth. By the middle of that century it was booming.

"With the industrial innovation of the 19th century," explains the historian, "you suddenly needed factory buildings, housing, and the viaducts and stations needed for the railways. All made out of bricks."

And Kent, just as it is today, was conveniently well positioned to benefit economically from being so close to the heart of the building work being undertaken - London.

Coupled with its transport links and geology it took full advantage of the opportunity.

"Bricks are heavy," adds Mr Cufley, "and while there were roads, they weren't good. The advantage north Kent had was the Thames. So a lot of the big brickfields were along the river's banks so they could sail them into the city.

"Also, it has clay with a chalk content that makes the London Stock bricks - the yellow bricks traditionally used in buildings. "They may not be very attractive, but they were the mainstay of the industry.

"Red bricks come from slightly different processes and clays and it depends where in the county you were as to what sort of bricks you made.

"Going down towards the Weald area they would have been red because of the iron content in the clay.

"In Wrotham, for example, you get a gault clay, which gives you a fine grained yellow brick."

From Sevenoaks to Swale, Tunbridge Wells to Thanet, the county saw brickworks spring up. Ashford, Medway, Folkestone and Crayford were also hot-spots as the demand for housing for workers locally rocketed.

And for the entrepreneur, the opportunities to cash-in were too good to miss.

George Smeed left school with little to no education. In fact, he could hardly write his name. In early adulthood he slept under hedgerows and made a pittance from selling potatoes and rabbit skins.

Yet, by the time he died at the age of 70 in 1881, he had amassed a fortune of in excess of what today would be worth £20million.

It was from the brickworks he created in Sittingbourne, after scraping up enough money from various odd jobs, that a vast brick-making empire was born - providing the building blocks of Victorian London and being used in buildings such as Buckingham Palace and the Tower of London.

At its peak, in 1877, his firm, Smeed Dean, was churning out more than 60million of the distinctive yellow London Stock bricks; making his firm the biggest in the county.

"When brickmarks were introduced in the 1850s," explains David Cufley, "SD was on the bricks and all the brick layers, even up to modern times, would recognise SD as being Smeeth Dean - and they would refer to the letters as also standing for strength and durability."

The proof is in the pudding - and a stroll around London will reveal many of the Victorian buildings made from the fruits of the firm’s labour.

And it was hard labour too.

Many brickmakers in rural brickfields would employ their families - with children as young as six or seven routinely used to help the process to meet the demand. And being paid a pittance in the process.

During much of the 19th century, the industry was seasonal - running from April to October. The clay being dug locally in the late autumn and then left during the winter for the weather to break down soluble materials.

Adds David Cufley: "It was hard and dirty work - especially during the summer, as you were working all daylight hours. "Towards the 1870s there are a lot of reports complaining about the hard work the children were being made to do - carting wet clay about, lifting loads. I wouldn't like to do it.

"But it would have provided jobs for thousands of people. However, they're under-represented. In the census back in these times, you'll get a brickmaker listed, but not the five other people in the gang working on the bricks. They'll be listed as a wife or son of a brickmaker or labourer. It disguises the sheer scale of it all.

"There were a lot of brickmaker strikes and fights and riots all concerning a demand for higher wages."

But the brick industry evolved quickly.

As more money was invested in machinery to simplify the process, by the late 19th century Kent's brick industry was already on the wane.

In Fletton, near Peterborough, the 'Fletton brick' was fast becoming popular - and the focus shifted from the Home Counties as the variety under cut the prices.

Explains the historian: "It's all to do with the type of clay there - it has a carbon content which allows them to burn a lot cheaper and railways brought them down to London. And that really started to kill off the Kent brickfields by the 1890s.

"By the time of the First World War - a lack of labour meant the rural brickfields started to close down.”

Ironically, for an industry designed to help Britain build, it would go on to be built on itself.

Smeed Dean bricks are still made in Sittingbourne (it is now owned by Austrian firm Wienerberger, the world's biggest brick producer) - but in far smaller numbers and primarily for the restoration of buildings which used its bricks when they were first built.

The legacy of the industry lives on with Sittingbourne Football Club using the nickname The Brickies.

But the rest of the industry has mostly disappeared - some clung on into the mid-to-late 20th century, but most fell by the wayside. Although if you know what you're looking for you can make an educated guess as to where they once were.

"When you dig your garden, I'll often ask people I'm giving talks to," adds the historian, "what do you encounter - and they'll say they occasionally find bricks or really hard clay. That's the first sign your house may have been built on an old brickfield.

"When you're out and about, look at the lie of the land. See if there's any dips.

"In the Sittingbourne area there are some roads you drive along them and you're above the builds either side - not solely because of the marshes and flood plains, but because of the extraction of clay for the brickworks."

Perhaps remarkably, no museum dedicated to brickmaking exists in the county.

Which means an industry so dominant 150 years-ago faces the very real prospect of having no lasting reminder.

Except, of course, for the buildings in each of our towns and cities which it helped create.

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