[time-nuts] Remove Pictic boards from envelopes
jimlux at earthlink.net
Tue Aug 10 22:55:25 UTC 2010
Alan Melia wrote:
> Pencil?? only us oldies know what that is....... it is surprising the "lead"
> pencil hasn't been banned under RoHS :-))
> Alan G3NYK
I don't know that "lead" (as in the element) has ever been used in
pencils.. I read a fascinating book on the history of the pencil a few
years back.. it described how graphite (the mines of Cumberland were
famous for graphite with good writing/drawing properties) was called
plumbago (lead ore) because chemical analysis didn't really exist and
the dense black substance seemed to resemble lead.
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