wrote: ,(clip) every one, without exception, of the
email warnings I have received with serious, unproven concerns that urges me
in BOLD CAPITAL LETTERS to send copies to everyone I know has been found to
be a hoax. (clip)
^^^^^^^^^^^^^^^^^^
Bob, how do I know that THIS is not a hoax? BG
Lyndell, Snopes doesn't say it IS a hoax. They leave the question open.
Bruce, the story about the oily rag on the bench is likely to be untrue.
Or, if it is true, it is certainly not due to spontaneous combustion.
Possibly a cigarette or some welding or grinding sparks could have
contributed.

Spontaneous combustion occurs from slow oxidation, which can cause the
temperature of a mass of fuel (oily rags, wood chips, etc) to rise.
Increasing temperature increases the oxidation rate, causing the process to
accelerate. However, a rag lying in open air probably loses enough heat so
the ignition temperature is never reached. (And certainly not in the time
for a single phone call.)