Guru was privileged to be invited to the Metropolitan Police Crime Museum recently.
The facility is not open to members of the public, but is used as a lecture theatre for the curator to lecture police and like bodies in subjects such as forensic science, pathology, law and investigative techniques.
It features many weapons used in real-life crimes, such as the gun used by Ruth Ellis - the last woman to be hanged in the UK - to kill her lover.
The museum also displays gruesome items like the bathtub and cooking pot used by serial killer Dennis Nilson to dismember and boil his victims.
But Guru was most intrigued by the museum curator's insistence that the Met Police know for certain the identity of Jack the Ripper.
The museum has recently come into possession of book called The Lighter Side of My Official Life, written by the head of the CID Dr Robert Anderson and heavily annotated by the officer in charge of the case, Chief Inspector Donald Swanson.
The pair were in no doubt about the identity of Jack the Ripper, claiming he was positively identified by the case's only eye-witness (who ultimately refused to testify against a fellow Polish Jews) as Aaron Kosminski.
After this identification which suspect knew, no other murder of this kind took place in London.
In a very short time the suspect with his hands tied behind his back, he was sent to Stepney Workhouse and then to Colney Hatch and died shortly afterwards - Kosminski was the suspect - DSS.
A barber and resident of Whitechapel since 1882, this was a man with an extreme hatred of women, especially prostitutes. Kosminski had strong homicidal tendencies and a history of brutal crimes. He was described by police as a self-abuser (he masturbated), he drank from sewers and ate scraps from the gutter.
As Swanson remarked, after Kosminski was identified, the murders ceased, and ultimately Kosminski died "demented and incoherent".
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