Death by wallpaper?

On your left, Napoleon Bonaparte smiling for his portrait. On your right, the Emperor of France again portrayed - only this time, through his death mask. The latter was created shortly after his death on or before May 5, 1821, and probably shows better than the paintings, the commanding features of the Little Corporal.

Ever since Napoleon died - in exile, on the island of St. Helena in the South Atlantic - there has been speculation as to the cause of his death. A few days prior to his death Napoleon had asked his doctor make a full examination of his body, particularly of his stomach - and it appears that a perforated stomach ulcer had turned cancerous causing the emperor's rapid deterioration.

This was confirmed by the doctors who conducted the post-mortem.

NO, SAID STEN, HE WAS MURDERED!

However, in 1952, Swedish dentist Sten Forshufvud concluded from the published account of Napoleon's death that Napoleon had been murdered and sought to prove it.

Fortunately, a number of Napoleon's staff had kept locks of the Emperor's hair, which sometimes came up for auction and when this happened in the 1960s, Forshufvud otained a sample and turned to Glasgow University forensic scientist Professor Hamilton Smith, who had developed the nuclear techniques to record very small levels of arsenic.

Using these techniques it was shown that small quantities of arsenic were present in Napoleon's hair - supporting the theory that the Emperor might have been poisoned without detection by slowly exposing to small quantities of arsenic. Forshufvud concluded that Napoleon had been murdered - and even named a suspect: the Comte de Montholon.

BUT THERE'S ALWAYS A BUT ...

However, in 1980, Dr David Jones on BBC Radio, suggested a more convincing explanation. Rather oddly, he asked if anyone knew the colour of Napoleon's wallpaper on St Helena. And it turned out that he had connected Napoleon's death with something called Gosio's Disease.

It transpired that, during the nineteenth century, there had been a number of mysterious cases of arsenic poisoning in which some people became ill but others died. Arsenic was found in their bodies and foul play was sometimes suspected although in many cases deliberate poisoning did not seem possible. In 1893 an Italian Biochemist called Gosio worked out what was happening.

SCHEELE'S - NOT SOYLENT

He pointed the finger at a colouring pigment called Scheele's Green - something that had been used in fabrics and wallpapers since around 1770. It was named after its inventor, the Swedish chemist Scheele who invented it. The bright green pigment was easy to make but under certain circumstances, the copper arsenite could be deadly.

Gosio discovered that if wallpaper containing Scheele's Green became damp and then became mouldy, the mould could carry out a chemical process to get rid of the copper arsenite. It converted it to a vapour form of arsenic, normally a mixture of arsine, dimethyl and trimethyl arsine which was very poisonous.

If Napoleon's wallpaper in that damp old house on St. Helena had been green, it could possibly have contained arsenic, and this could have been the source of the arsenic in the hair sample. Napoleon, he suggested, might have been an early victim of Gosio's disease.

Amazingly, a piece of the actual wallpaper was discovered in Norfolk, England, decorated in the imperial colours of gold and green. The green pigment did indeed contain arsenic and it now looks very much as if Napoleon might have been a victim of Gosio's disease, poisoned not by the British authorities, but inadvertently by the British wallpaper makers.