A letter from Jack the Ripper jeering at the authorities for their failure to capture him and warning that he would be "on the job soon" is to be made publicly available for the first time today.
The letter has been passed by London police to the British public record office at Kew in south-west London where it is to go on exhibition. It is expected to fuel the controversy over the unsolved vicious murders of five women in Whitechapel, in the east end of London in the autumn of 1888.
Arguments over the true identity of Jack the Ripper have raged between the impossible and the improbable for more than a century and include the claim that Prince Albert, the grandson of Queen Victoria, was indirectly involved.
Police archivists said the newly released letter sent at the height of the hunt for the Ripper to Dr Thomas Openshaw, the curator of the pathological museum at the London Hospital, Whitechapel, was directly linked to the best known letter in the case which was sent to the authorities along with half a human kidney.
The Openshaw letter was sent to the doctor who carried out the police examination on the kidney to establish whether or not it was genuine. Signed by Jack the Ripper it jeers at the results of the doctor's examination which had been widely reported in the newspapers. He had found that it was in a similar state to the kidney that had been left in the body of the last victim of the Ripper. It was a "ginny" kidney of the sort found in an alcoholic, it belonged to a woman of about 45 and had been removed within the previous three weeks, he reported.
The letter jeered at the doctor in mock cockney tones: "Old boss you was rite it was the left kidney I was goin to hoperate agin close to your ospitle just as I was going to dror mi nife along of er bloomin throte them cusses of coppers spoilt the game but I guess I wil be on the job soon and will send you another bit of innerds
Jack the ripper
O have you seen the devle with his mikerscope and scalpul a lookin at a Kidney with a slide cocked up."
The British had a prototype of the Enigma code machine more than a decade before the second World War, it emerged in other papers released at Kew. Documents also showed that secret government trials were carried out to create gas masks for dogs used by the army in the war.