TODAY is the feast of St Bartholomew and in rural Yorkshire, it was known for two things - first, ancient weather lore said that the season's dew arrives on this date and second, it was the occasion for feasts and fairs, one of the survivors being Witton feast in Wensleydale with its curious Burning of Owd Bartle.

First, the dew. Most of us are familiar with the appearance of dew on the grass and cool surfaces, though we are seldom aware of it during the hot summer mornings. As autumn approaches, however, lawns and verges are covered with a fine layer of moisture. enough to thoroughly soak our shoes and to make us aware of the sheer number of spiders' webs in the hedgerows. So what is dew?

It is moisture which materialises in the form of tiny droplets of water. It settles on plants and objects such as car roofs, when the earth cools rapidly after the heat of the day.

The autumn combination of high humidity followed by long clear nights is ideal for the production of dew, and it appears when the moisture, which is naturally present in the air, condenses to reveal itself on a variety of cool surfaces. This occurs when the air temperature falls until it reaches what is known as the dew point.

If there is a layer of cloud, then this cooling will not occur and dew will not form. The presence of dew therefore means the night has been fine, dry and clear with little wind - and a bonus is that the day which follows will be fine and dry.

There is a piece of old weather lore which says, "With dew before midnight, the next day is sure to be bright", while another adds, "If the dew lies plentifully on the grass after a fair day, it is a sign of another."

It was Aristotle who said, "Dew is produced in serene weather and in calm places."

Years ago, people liked to walk barefoot in dew because they thought the pure liquid would cure, or at least ease, various complaints of the feet, while the more daring would roll naked in the morning dew for similar reasons, often in the belief it would cure skin diseases. May dew was thought especially beneficial, with some women thinking it made them more beautiful.

Catherine of Aragon was one such. With 25 of her maids, she would go gathering small phials of dew to store for this very purpose. I am told, too, that the farmers of ancient Slavonia would bathe their cows in dew, thinking it helped to keep away witches and evil spirits.

One benefit of dew is that it provides moisture for the landscape when there is no rainfall, and this was recognised years ago by farmers who constructed dew ponds. In areas where there were no streams or springs, these provided drinking water for livestock, and because these ponds had no outlets or inlets, they never ran dry.

Though the original dew ponds were formed by nature, farmers soon realised they could construct them.

Up to 30yds in diameter, a dew pond is a saucer-shaped hollow up to 6ft deep in the centre. Sometimes called a sheep pond or a clay pond, it can be created by lining the hollow with stones, rubble and straw beneath a covering of clay. When it is full, these ingredients help to keep the water cooler than the ground.

Condensation in the night air helps to maintain the supply of water in a dew pond, and the fact that the pond is open to the elements in the summer means its water is never too dangerously cold to be enjoying by sweating horses.

Fairs and feasts held on St Bartholomew's Day were often known as Bartle fairs or Bartle feasts, Bartle apparently being a shortened version of the saint's name. A gigantic fair used to be hell at Smithfield in London, while a horse fair, said to be England's oldest, was held at West Ardsley, near Wakefield, along with others around the country.

One of these was at West Witton in Wensleydale, sometimes called the St Bartholomew's Day fair, but more locally known as Witton feast. Now, it is usually held on the Saturday nearest his feast day.

Witton feast ends with an ancient ceremony called the Burning of Owd Bartle, and though the village parish church is dedicated to St Bartholomew, it seems unlikely that an effigy of him is burned. One possibility is that Bartle may be linked to the Giant of Penhill, under whose shadow the village lies, or he might be associated with the sun deity known as Baal.

Yet another theory is that Bartle was a horse thief whose crimes are still remembered and a further possibility is that the ceremony stems from pagan times when the last cut sheaf of corn was thought to contain the corn spirit. It was burnt to destroy the evil of that spirit.

In East Witton's case, the effigy of Bartle is carried in procession to the accompaniment of a chanted verse to the outskirts of the village where it is ceremoniously burned.

Rare bird

I have received a note from the RSPB which highlights the remarkable return to Yorkshire of that rare bird of prey, the red kite. Six pairs have nested in Yorkshire this year, and eight chicks have been reared, a remarkable outcome for a bird which became extinct in England in 1870 and in Scotland by 1890. Once this was a common bird of prey in England, even in towns where it helped to clear away carrion left in the streets, but on the hills and moors, it was shot because it was wrongly thought to take game chicks.

One of the bird's features is its ability to soar and glide over the landscape, and this gave its name to the child's toy known as the kite.

A few pairs did survive in central Wales, however, and resulting from their protection, their numbers increased to about 180 pairs. The spread of red kites in central Wales, however, is insufficient to generate re-colonisation in the rest of Britain, and so the re-introduction of this bird of prey has required a helping hand.

It all began in 1989 with an initiative from the former Nature Conservancy Council and the RSPB. Young red kites were released in the south of England and northern Scotland, to be followed by further release schemes in the Midlands (1995) and central Scotland (1996).

Fortunately, these plans received the co-operation of landowners, gamekeepers and farmers, and this has resulted in the current success in Yorkshire, together with an increase in the red kite population of Wales.

The high number of chicks produced in Yorkshire this year has astonished the experts, particularly as the spread of foot-and-mouth disease and the resultant limitations upon access to their breeding grounds, has prevented comprehensive monitoring.

It is hoped that this heralds the return of a sustainable wild population of red kites, and the latest news is that 42 young ones have been released into the wild from a secret location on the Harewood estate, near Leeds.

The Yorkshire red kite project is a partnership between English Nature and the RSPB, with financial backing from Yorkshire Water and Integrated Waste Management via Enventure Northern, and the project enjoys the active support of the Harewood estate.

Grain in dialect

I have come across a curious word meaning stream, though it is also used to indicate a branch of something. The word is grain, and this is often given to small streams rising on the moors and fells. Years ago, I remember cycling with friends in the northern Pennines, and our route took us across an area known as Grains o' the Beck.

According to Sir Alfred Pease in his Dictionary of the North Riding Dialect (1928), the word is sometimes wrongly shown as "grange" in some names, such as farms. It does seem, however, that a grain is a small branch of a stream, one which eventually becomes larger by uniting with others, but the term can also be used to describe the small branches of trees.

Contributing to Sir Alfred's book, Maj J Fairfax-Blakeborough goes on to say that the origin of grain in this sense is little to do with corn, but may come from the Old Norse greina, which means to divide, or even the Swedish glen which refers to an angle. He refers to one area of elevated land which divides to branches of a beck on the North York moors, and this is called Helwarth Grains.