Maev Kennedy , arts and heritage correspondent

Monday September 11, 2000 Chemical analysis of a sealed 17th century bottle found in the foundations of a Surrey house has revealed not a secret Jacobean wine stash but a revolting folk charm against witches. It is made of human urine, pubic hairs, an eyelash and a handful of bent pins.

The witch bottle, as such charms were known, still contained almost half a pint of 300-year-old urine. Witch bottles were made by people who believed their illness or misfortune, the death of family members or livestock, meant they had been cursed.

The bottles were intended to turn the curse back on the witch. Although the urine was that of the victim, it was believed there was such a strong link between the curser and the cursed that the charm would work on the witch, for as long as the bottle remained sealed.

Alan Massey, a retired organic chemist from Loughborough University who carried out the analysis, said: "In this case the curse was intended to make the unfortunate object of it feel as if they were weeing with a bladder full of bent pins."

His work, published in the journal Current Archaeology, has proved the folk belief that such bottles did contain human urine. Although more than 200 witch bottles, dating mainly from the late 16th to the early 18th centuries, have been found, almost all were broken or empty.

This witch bottle was found sealed with all its contents intact despite being buried more than 300 years ago in the foundations of a house which was demolished in the 18th century near the ramparts of the castle in Reigate.

It was discovered by the archaeologist David Williams, who jumped to the obvious conclusion about a sealed wine bottle. "I managed to get a local vineyard interested and they arranged to open the bottle, test the contents and possibly organise a tasting," he said. "When the cork was pulled there was a rather alarming hiss of escaping gas. They could find no trace of alcohol - or indeed anything organic. I then poured the contents through a strainer, and out fell all these pins and other bits and pieces."

The bottle went to Mr Massey, who was already testing finds for Brian Hoggard, a postgraduate student from Worcester University, who is completing a thesis on witch bottles. He has traced hundreds of reports of bottles found in the ruins of hovels and mansions.

The earliest finds date from the late 16th century in Nottinghamshire and the most recent from a mid 19th century cottage in Pershore, Worcestershire. "It was believed that they would cause such agony that the witch would come to your door and beg to be released from the curse," he said.

He also analysed the nine brass pins and proved that they had been bent as a single bunch. Bending the pins was a symbolic killing, as well as intended to torture the witch.

Mr Hoggard found it impossible to trace the occupants of the long-demolished house in local records, never mind discovering whether they suffered any exceptional bad luck.