The ‘From Hell’ Letter
In 1888, Jack the Ripper sent the London police a letter titled "from Hell." The ‘From Hell’ Letter contains half of a human kidney. Many serial murderers saw it as the most reliable and authentic means of contact. This kidney came from his victim, who had written the letter. The letter, which was on the paper, was then misplaced. It is stated that it was either taken or thrown away, leaving no proof for this story.
The ramifications of this tragedy are enormous. For one thing, we could have used current tools to determine if the kidney originated from one of Jack's victims. If it did, we'd be able to verify the letter itself. Second, it's always conceivable that some trace was left on the paper, allowing us to ultimately solve the Whitechapel murders. Instead, this crucial evidence was most likely taken or discarded, leaving us as perplexed as the Victorians.