Billy the Kid shatters the water jug on the desk where Davy Jones, Micky Dolenz and Michael Nesmith are seated. The drinking glass is upright. Within moments, all the remains are missing, except the glass, which has now toppled over.
The historical characters bear very little resemblance to the men they're based on, whether in appearance or personality.
Billy the Kid is said by multiple characters (including himself) to have begun his gun-fighting career in 1882. Billy had begun taking part in firearm-based violence in 1877 or 1878, and was killed on 14 July 1881.