Items

"From Hell" letter
A letter sent to George Lusk, the head of Whitechapel's Mile End Vigilance Committee, on October 16, 1888. The message was supposedly accompanied by half of a kidney (purportedly from Catherine Eddowes), which was later thought to be a prank.
"Saucy Jacky" postcard
A postcard, sent to the Central News Agency on October 1, 1888 and signed "Jack the Ripper, which takes credit for the murders of Elizabeth Stride and Catherine Eddowes the previous night.
"Dear Boss" letter
A letter, written in red ink, mailed to the Central News Agency between September 25-27, 1888, and then sent to Scotland Yard (London Metropolitan Police), claims responsibility for the murder of Annie Chapman and includes details from the crime scene that were not known by the public. The content of the message and threats of future victims implied that the author of the note could be the real killer. The famous pseudonym "Jack the Ripper" comes from the signature line on this letter.
"Anonymous letter to City of London Police about Jack the Ripper"
This anonymous letter was sent to the City of London Police in October 1888, accusing "Jekyll and Hyde" actor Richard Mansfield of committing the Jack the Ripper murders.