It is impossible to talk of flint without mentioning chalk, since they are bedfellows in the earth's crust, occurring together on the Salisbury plains, through the Chilterns to Norfolk, Lincolnshire and the Yorkshire Wolds, with an eastern corridor tunnelling through Surrey to the white cliffs of Dover. Inside these great layers of chalk, the flints occur like huge black oyster pearls. They are nodules of silica that formed around ancient sponge fossils and seashells.
But it is on the borders of Hampshire, Wiltshire and Dorset that houses made of these stones become unexpectedly lighthearted. Suddenly you find cottages of chequerboard patterns, made with blocks of greensand, chalk or limestone, a close relation, for the light squares, and flint for the dark ones. Others are covered in brightly contrasting horizontal stripes made in alternating bands of flint and a lighter stone.
Villages in the Wylye valley sparkle like architectural party decorations among the Wiltshire downs. None more so than in Wylye itself, where Yvonne Ranken's cottage is one of the prettiest. A confection of chalk and flint under a thatched roof, facing the church of St Mary the Virgin, it owes its very existence to its good looks. It was shot through with rat holes when a previous owner found it and rescued it from the brink of dereliction. 'When it came to our turn to buy it we were just enchanted,' says Yvonne Ranken. 'The chequerboard is just lovely. It's called a diaper pattern.'
She knows little about the origins of the house, which had been part of the Pembroke estate, lands of the Herbert family who live at Wilton House, because the deeds were lost when the Pembroke archives went up in flames. A date etched on one of the internal beams reads either 1358 or 1558, no one is sure which. But she believes it must once have been the village bakery. It has two ovens, one either side of the walk-in fireplace in the sitting room, from which a vast chimney breast funnels up through the bedroom and loft.
But, as so often is the case, there is a price to be paid for the privilege of living in a three-dimensional chessboard. The paler chalk squares are much softer than the darker flint squares, attracting damp when the weather is wet. 'You could almost pick the chalk off with your fingernail on the outside,' says Yvonne Ranken. 'But the walls are thick, and inside we stay nice and dry.'
Further along the valley at Great Wishford, Marjorie Paskin has just had a coat of old-fashioned limewash applied to the chalk on the outside of her semi-detached cottage - appropriately named Chequers. The treatment should heal the wounds in the chalk caused by the frost of the last two winters, yet still allow the walls to 'breathe' in a way that modern treatments would not. Boiled linseed oil, or even milk, with hot lime poultices applied to stains, are other rescue remedies. Conservationists working at Woburn Abbey have been experimenting with different solutions on sections of clunch wall in the stable block. (Clunch is a poor relation to pure chalk, since it is harder and contains tiny fragments of shell and sandstone).
Though its softness has its drawbacks, pure chalk is a wonderful raw material for elaborate windows and church statues. The trouble is that new clunch and chalk are very hard to come by. The Totternhoe caves, near Dunstable, Bedfordshire, once stretched for miles - the miners grew thyme and mint to disguise the smell in which they worked. One supplier still has the rights to clunch extracted there, though many of the caves are closed. And once mined, the rock has to be left to 'cure' for at least one winter.
It is ironic that cottages which were built centuries ago for agricultural labourers, who may have slept 10 children to a bedroom and had only outside sanitation, have now been so joyously colonised by the middle classes. Lady Paskin's house falls into this category, being - as her researches prove - at least three centuries old. She came across a 1698 map, which she has since given to Trowbridge Museum, plotting the houses in Great Wishford and showing them to be virtually unchanged today. But the income and work of the inhabitants have changed, though the May ritual of decorating houses with oak boughs and oak apples, to celebrate the villagers' rights to gather dry kindling in woods belonging to the Earl of Pembroke, carries on much as it did before.
One who enjoyed translating such ancient folklore and local ritual into the language of architecture was Edwin Lutyens, who worked wonders with flint and chalk at a house called Marsh Court at Stockbridge, Hampshire. 'A joyous expression of the materials of the locality, chalk, flint and tile - marshalled into large and simple shapes in harmony with the landscape,' is how Country Life described it in 1932. 'Lutyens, versed in the love of old country craftsmen, incorporated their learning into his architecture.' The story is that the house was built around a vast column of naturally occurring chalk, which was left in situ and was carved into the base of a billiard table.
The restoration of this house (the chalk had been treated with milk but has since decayed badly) has presented problems to the architects, Purcell, Miller, Tritton, because pure chalk is now so hard to find. The timetable for the project has had to depend on the finds of odd blocks at a lime quarry some way away.
'The flint, of course, is undamaged. Pebbles of flint were simply left in the chalk wherever they naturally occurred, which is quite fun,' says Garry Seymour, the architect managing the project.
Though flint stones occur within the comparatively soft beds of chalk, they offer indestructibility as their chief virtue, as early man discovered when he used them as weapons and tools. At Grimes Graves on the borders of Norfolk and Suffolk you can walk down into the shaft of an early flint dig and see the strata of chalk and flint. The angled blow of a red deer antler was used to cut or 'knap' the flints as spearheads.
Knapping is really the only way to discipline a material which comes in as many shapes and sizes as the pebbles on a beach. Cutting a flint exposes the core like a hard dark yolk within a pale brittle egg. In the 13th and 14th centuries, knapped flints were cut into smart squares and placed together to turn church and cathedral walls into rich dark tapestries of stone.
Humbler dwellings made of pure flint use uncut stones. Their charm lies in the apparent carelessness with which they have been buried into the mortar, huge knobs alongside small nuggets, with bricks to provide the square trim to the doors and windows. And nothing but the best old- fashioned lime mortar will do to hold the flints comfortably together. Adela Wright, in her book Craft Techniques for Traditional Buildings, says: '(The mortar) must be stiff enough to prevent the flints rolling out of position; the consistency should be similar to creamy butter, firm but slightly sticky.'
Anyone can learn how to make lime mortar. It isn't hard. Day courses at the Lime Centre, at Morestead near Winchester (see the index of specialists on page 67), start with everyone slaking burnt lime lumps in tanks of cold water, then watching the chemical reaction cause the mixture to cloud and boil to a thick putty. This is followed by a hands-on chance to use it and find out how versatile it is. 'At one time every village had its limestone pit and its kiln making burnt lime,' says
the course director, Bob Bennett.
Building with flint is a far greater test of patience, having more in common with trying to teach an unruly dog to sit up and beg than with standard building skills. Richard Deane, a Salisbury Cathedral stonemason who also repairs historic buildings locally, recalls seeing a wall being built and then watching it gently collapse a moment later. Usually a wall will be made with thick footings, perhaps 3ft deep, with two outer skins tapering slightly at the top filled with rubble. 'Building a flint wall is incredibly difficult because of the shape and weight of the stones,' he explains. 'Flint doesn't lie down nicely in the mortar and it is totally non-porous.'
This means that the unruly dog then has to learn to balance marbles on its head. 'Flint doesn't create the sort of suck that brick does in a wall by drawing some of the moisture from the mortar and helping it to set. So you can't build too much too quickly or expect it to hold together well.' If the weather is bad it can take days to harden, so builders have to return each day to poke the flints back into position before they slide out. Neither does flint turn corners, hence the embroidery of brick to provide the hard edges. Medieval masons in Norfolk got round this by building circular church towers.
Norfolk remains one of the great strongholds of flint. Michael Knights, the county council's conservation officer, says: 'There are so many different types of flint. The lovely black ones from this county, which is the deep mined stuff, was used to make great medieval churches, and then used again to make 19th-century copies. Then there are the pebbles that were picked off beaches or fields. Those that were dropped by the glaciers are very grey white and much bigger.'
Few books have been written on flint. Few great names have praised it. And few knappers remain to pass the skills on. Flint and chalk haven't undergone a revival in the same way that other vernacular styles have done. But, just as brown bread found its admirers again, there is no reason flint shouldn't do the same.
HOUSES FOR SALE
Norfolk gave its early inhabitants nothing better to build with than rough flints which they used to great effect, erecting cathedral-sized churches in the tiniest of villages. Pebbles plucked from the countryside were piled into cottage walls.
A traditional flint cottage set back from the sea in the village of Stiffkey is the Old Stores, built with random flint walls under a pantile roof in around 1820. It has four bedrooms, an artist's studio, elaborately stencilled interiors and gardens running down to the River Stiffkey, all for pounds 175,000 through Strutt & Parker.
Moving down through the flint and chalk belt into Suffolk there is a former vicarage at Ashbocking, near Ipswich, which owes much of its appeal to the close flintwork on one flank, edged in white brick. In need of updating, it has five principal bedrooms, eight service bedrooms and six acres. The price is pounds 295,000 (Strutt & Parker). A typical brick- and-flint cottage in good condition at Shimpling, near Bury St Edmunds, is on the market with Hamptons at pounds 110,000. It comes with three bedrooms and cottage garden.
Oxfordshire, too, is splashed with flint and chalk in the south east, but it is in the chalk heartlands of Wiltshire that one of the finest brick and flint houses on the market this year is to be found. Stockton House, Stockton, is a Grade I Elizabethan country house with alternate rows of limestone ashlar and knapped flints, creating startling horizontal stripes that make it look like an enormous tiered cake. It is set in 40 acres with paddocks, parkland, stabling, staff quarters and swimming pool.
The room that knocks the breath away is the Great Chamber, with oak panelling beneath a plaster ceiling swarming with flowers and animals, and a fireplace worthy of a cathedral altarpiece. The nursery and staff wing is chequerboard flintwork. Seven firm offers were made at Savills' asking price of pounds 700,000, and the house has now been sold.