In article ,
Andy Dingley wrote:
A similar thing is a Chinagraph pencil, which is still pretty common.
They're very similar to use (they need a lick before they'll write
straight off on a low-friction surface). Not indelible though.

Used to be common in the days of tape editing. I'd have said the shiny
back of some tape was a fairly low friction surface - as is glass - but
I've never needed to lick one.

--
*When the going gets tough, use duct tape

Dave Plowman London SW 12
RIP Acorn