In a few hours' time he is going to die, 'John Williams told his wife'. The terrible thing is there is nothing I can do about it."
It was 4am and John Williams and his wife Dora were sipping tea in the kitchen of their farmhouse in a remote village near Redruth in Cornwall.
There was to be little sleep for either of them that night as they endlessly discussed the dream from which Williams had just woken ... a dream which apparently forecast in chilling detail the assassination of the prime minister of England.
As dawn broke on the morning of May 11, 1812, Prime Minister Spencer Perceval slept fitfully at the home of a friend in London's Greenwich 270 miles away.
Could he also have had some indication that at 11am that morning he would be the central figure in a tragedy which would stun British political life for a decade?
John Williams, a down-to-earth tenant farmer with absolutely no interest in the shadowy world of the paranormal, certainly claimed to know, and 200 years later his dream remains a classic prediction for which there is no rational explanation.
It is a stark reminder that things are seldom what they seem and that time as we know it might possibly contain other dimensions which enable us to look both forward to the future and back into the past. But at the moment all this remains a rather esoteric theory.
Today John Williams could have passed on his fears by phone, e-mail, text or could have contacted the police but in 1812 it could take three days to travel from Cornwall to London. And he had only seven hours.
Desperate to tell someone about his dream he waited until 7am before knocking on the door of the local doctor who had recently returned from London.
When he described the man he had seen in his dream the doctor told him: "You have described Spencer Perceval as if you had been in the room with him."
The pair then went to the village church where Williams told his story yet again, this time to the vicar. Both witnesses were now so impressed by the story that they independently wrote an account of the dream, including Williams' description of the assassin.
It was decided that Williams and the vicar, the Rev. William Assam, would take the next mail coach to London. The vicar later wrote: "I had a strange feeling concerning this man's dream which made me convinced that the authorities should be made aware that there was the possibility of a violent attack on Perceval.
"Williams was at pains to point out that he was certain that the murder attempt would take place in the next few hours but I felt he could not be so precise on a matter of this nature.
"We discussed the possibility of using the semaphore system which passed military messages up and down the country but the problems involved in getting permission were so great that we felt we just had to press on to London as fast as we could and hope we were not too late."
They were. When the men finally arrived in London they found the capital in uproar. The prime minister had been assassinated in the lobby of the House of Commons two days earlier.
The clergyman who had a relative who was an MP, arranged for the farmer to visit Westminster — a place he had never seen before. But immediately on arrival, Williams walked in and pointed to a spot in the lobby and said: "This is where the prime minister was shot in my dream.
"From that pillar I saw a man come forward with a pistol in his hand." And that was precisely what had happened...
Williams' story came to the attention of Spencer Perceval's brother-in-law, the Earl of Harrowby, who met the Cornish farmer and provided an astonishing sequel to the story.
He said that the prime minister had stayed at his Belgravia home the night before he died and had apparently had a terrifying dream, identical in all major points to that of John Williams.
In the dream he had seen himself shot in the lobby by an assassin. Lord Harrowby later wrote: "When he told me about the events I urged him not to go to the House that morning but he insisted and I never saw him alive again."
How could two men have virtually identical dreams of death? Why should a farmer in remote Cornwall be chosen to witness a preview of a national calamity?
Of course it can't be explained in rational terms but some experts believe that the power of sleep may sometimes seem to open secret doors of perception to give a glimpse, if only for a moment, of what life has in store.