Good drugs/Bad drugs?

[Burgess, John]

LSD, in its rye-ergot form, is a pretty natural drug, at least as natural 
as peyote or marijuana or amanita.  As a fungus of the rye plant -- which 
was a staple in the central/northern European diet --
the opportunities for accidental injestion were rife.  

According to some interpreters, entire villages would sometimes be 
overcome by the "natural form" of LSD, leading to events that were seen 
as absolutely terrifying visions of the Final Judgement.  This syndrome, 
known as St. {can't remember who}'s Dance, is pretty well documented 
contemporaneously, though without (obviously) a causative agent.  There's 
some suggestion that ergot poisoning had a bearing on the Dance of Death 
(Todentanse) and its depiction in many woodcuts of the period.

Unlike ergot, though, coal tar isn't terribly useful unless and until 
it's run through some sort of chemical process.  Taken in it's "natural 
state," it's merely toxic, with no known psychogenic/psychodelic effect.