Date: Fri Feb 23 11:15:51 2007

Author: David Sturm

Subject: Re: Jearl Walker Molten Lead

I think the lesson to be learned here might not be the suggested
rudeness of a visiting demonstrator, but in internal departmental

I get the sense John, that you were told all this at the last minute,
whereas someone in your department had arranged the invitation
for Jearl, and clearly has known for sometime he would be visiting
and that he would be doing some of his well-known demonstrations.

This is something we often raise in professional concerns cracker-
barrels, where the instructional physicists like us are often told about
5 minutes before a class or lecture, that so and so would like the
demonstration that takes an hour to prepare, or some ingredient
that requires a few days' notice.

I know the moment I'd hear that Jearl would be visiting, I could
quickly look at page 63 of The Flying Circus of Physics to his own
comments about "dipping [his] fingers into molten lead" or view his
web page comments on why he stopped doing this for a long time.

Kail reports correctly how the small amount of lead used (and note,
he's not using lead powder, or lead shot, he has his own little vat-pot of
ready-to-melt lead) presents much less concern than an OSHA or
campus safety rep would be concerned with in person...

It's too bad that John (and others of us facing these same issues daily)
wasn't given enough lead time to allow this demonstration to be done.

An aside on that note about a chemistry professor encourage an
elementary teacher to get LNē and do "frozen graham crackers":
this is allowing injurious harm to a child, and child abuse. When we
do this at demo shows, ONLY the demonstrator is going to ever
put frozen Girl Scout Trefoil Cookies into mouth.... and both Roger
and I are very peculiar about doing this such that the cookie doesn't
have nitrogen in the holes, we break it (more surface area) and slosh
it around quickly, and whereas Roger washes it down with water, I
usually spit it out after blowing the "dragon breath" out nose and
mouth and say.. "Yuck, very stale" and swish down some
diet coke...

I'm MUCH MORE seriously concerned about those kids than I am Jearl
putting a couple very wet fingers momentarily into lead...

The campus safety officer should be notified about what the chemistry
professor has done... any parent of those children could sue right up
the "graham cracker" food chain back to the university...
David E G Sturm - - 1.207.581.1241
--Physics & Astronomy Instructional Laboratories
--Bennett Hall Lecture Demonstration Facilities
--Mainely Physics Road Show
Dept of Physics & Astronomy -- University of Maine
5709 Bennett Hall -- Orono ME 04469-5709