"hahahaha" -everyone else.
Quoted from July '07
Lynchburg College, Va
Yes indeed i do miss you governor's school for science, math, and technology.
and the reasoning behind this memory...
"
Having had first hand experience using that type of pencil ,"
the answer to the question is that in the old days the
filaments used in pencils were made of different material
than today's graphite which is charcoal colored and its
particles separate easily on friction with the paper surface
leaving clear marks. The old material did not leave much
of amark on the paper due to its high density. It was water
soluble and if left in a water filled container ,will dissolve
completely. On contact with water it changes color from
dark charcoal like color to violet blue. In order to leave a
clear mark on paper it was necessary to actually moisten the
tip of the pencil filament with your saliva ,the
resulting product behaved and flowed like ink.
http://www.madsci.org/posts/archives/1999-11/941497627.Sh.r.html
so now we know.
Add an ink-like, high-density pencil to my Christmas wishlist. Right below a vat of a non-newtonian liquid. Speaking of which, turns out that human (and probably other animals) blood is non-newtonian. Kudos to my brother for telling me about that.
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