Readers with a fondness for the mysterious and unexplained will doubtless be familiar with the case of the 19th Century enigma, Kaspar Hauser.
On 26 May 1828, an unkempt teenage boy appeared in the streets of Nuremberg, Germany. He seemed unable to express himself clearly but constantly repeated the sentence, "I want to be a soldier like my father was" and the word, "Horse".
Given pen and paper, he wrote the name 'Kaspar Hauser', but otherwise he appeared unwilling or unable to communicate. It was assumed at first that he had been living wild in the surrounding forests but, as he adapted to his surroundings, he told a story of being reared from infancy in a cramped cellar by an unseen jailer who suddenly released him into the Bavarian countryside, first giving him the letter and teaching him his one sentence.
The boy's story captured the imagination of 19th Century Europe, prompting increasingly far-fetched speculation about aristocratic or even royal connections. In the sci-fi mad 1950s, the story was resurrected with the theory that the boy might have travelled from another time or a parallel reality, or even another planet.
There is, of course, no such fanciful speculation about the 17-year-old found in Berlin last week, although his case does present several interesting puzzles.
The 17-year-old, who turned up at Berlin’s city hall, said he had been walking for two weeks but had no idea who he was or where he was from.
He told officers that he and his father moved to the forest about five years ago following the death of his mother and had lived off the land since, sleeping in a tent and remote huts.
He said his father had also died recently and that he had buried him in a shallow grave before setting off to find help.
Detectives said the teenager, who gave his name as Ray, spoke a little German, but his first language appeared to be English.
Hence, of course, the story's appearance in the British press. Unfortunately for those trying to help, the boy does not appear to know his parents' surnames and has no recollection of his life before entering the forest. The only possible clue to his identitiy is his fluent English; his German is described as 'basic'.
Since the boy's appearance on September 5th, nothing has been found to suggest an identity; the search is now being widened in the hope that someone outside Germany can provide a clue. With modern technology on his side, the authorities can be optimistic that this case, at least, may well be solved.
Kaspar Hauser was not so lucky. Amid speculation that he himself may have been responsible for concocting some of the many unexplained events that surrounded him, he died of a stab wound inflicted by 'a stranger' - or possibly himself - in 1833.
Hauser was buried in a country graveyard; his headstone reads, in Latin,
"Here lies Kaspar Hauser, riddle of his time. His birth was unknown, his death mysterious."