Story books suggest Napoleon Bonaparte died of natural causes in exile on the island of St Helena, writes REG LITTLE. But many people prefer the conspiracy theory: was he assassinated by poison?

It would have been something to boast about had nuclear engineer Brian Metcalfe been able to answer that question, 150 years after the Emperor's body was brought back to France to be interred in the Hotel des Invalides.

But at least Brian can claim he went some way to solving the mystery. He recalled: "I was involved in the measurements of strands of Napoleon's hair to determine whether he was poisoned by arsenic."

In fact, during his 48-year career at the Atomic Energy Authority in Harwell, Brian personally carried out the chemical analysis which might have proved beyond doubt that the level of arsenic in Napoleon's hair indicated foul play.

Everyone's hair contains a naturally occurring level of arsenic - fewer than ten parts per million. But when Brian carried out his analysis in the early 1980s, he found strands of Napoleon's hair contained three times that amount. However, pathologists claim the hair of anyone killed by arsenic poisoning would contain at least 80 parts per million. "The results were inconclusive," admitted Brian.

Other researchers have suggested that the high levl of arsenic in Napoleon's hair was linked to a compound in the heavy flock wallpaper lining a room where he spent much of his time on St Helena.

His investigative days are over now. He recently retired as the longest-serving employee in the Atomic Energy Authority's 2,000-strong workforce.

Born in Ripon, Yorkshire, he arrived at Harwell in 1950 armed with a school certificate, and started work as a scientific assistant.

Following two years on wireless duty in the RAF, he returned to Harwell to work on the Bepo test reactor, which provided the blueprint for Calder Hall, the first reactor in the world to produce electricity.

During the 1950s and 60s, Brian was involved in a variety of programmes transferring Harwell's new technology to industry.

They included irradiating diamonds for De Beers to change their colour for jewellery, measuring car engine wear from isotopes in sump oil, and tracking the movement of silt in sea navigation channels.

He later helped carry out important work on an X-ray system to be used in British Nuclear Fuel's Thorpe reprocessing plant. Now 65, Brian said: has been active in the community and recalled his initial astonishment when he was invited to attend a meeting of Harwell parish council to find councillors voting on a proposal to co-opt him as a member.

"I knew nothing about it until then," he said.

"But after some arm-twisting, I agreed to serve."

He was to remain on the parish council for 16 years, retiring as chairman in 1976.

"I believe I'm the last 'established' Civil Servant in the UKAEA as well as being its longest serving employee," he said.

"I have spent my career at Harwell and will miss its characters."

Apart from planning to become involved in council affairs at his new home in Shropshire, one of his pet retirement projects will be to dip into his family's connections with movie great Stan Laurel. The thin one from the Laurel and Hardy partnership was his first cousin once removed.

TALE OF AN EMPEROR

Napoleon Bonaparte (1769-1821), French Emperor, was a general in the Revolutionary Wars but overthrew the ruling Directory in

1799 to be dictator.

He married Josephine de Beauharnais, but in 1809 divorced her to marry Austrian emperor's daughter Marie Louise.

From 1803 he conquered most of Europe in the Napoleonic Wars but after the retreat from Moscow in 1812, he was forced to abdicate and banished to the island of Elba.

He resumed power but in 1815 was defeated by Wellington at the Battle of Waterloo and exiled.

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