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Date: | Wed, 13 Feb 2002 18:46:40 -0500 |
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Carl:
This sounds like it may be a souvenir. I once excavated a site on which we
found a lead Statue of Liberty and a Lead Eiffel Tower. As a kid I had a
lead Washington Monument with a mercury thermometer in it (what a great toy
for children, and that may explain a few things.)
Or, it may be a scientific toy. Recently we had a guy from Jefferson Labs
come into the Children's Museum to do a liquid nitrogen demonstration
(really "cool," if you get my "drift"). One of his props was a pewter cup,
known as a "Jefferson Cup" here in VA, known as a pewter cup
elsewhere. This pewter cup, while at room temp, had a dull thud when
struck, but after a minute or so in a soothing bath of liquid Nitrogen at
-196 °C the pewter cup rang clear as if made of the finest silver (well,
nearly so).
Here's their set up with the Jefferson Cup:
http://education.jlab.org/beamsactivity/6thgrade/hotandcold/overview.html
Here are some pages I found with the same experiment using an actual lead bell:
http://www.ph.utexas.edu/~phy-demo/demo-txt/4a40-10.html
http://www.physics.uiowa.edu/~dstille/chem/4A40.10.htm
http://www.physics.purdue.edu/demo/3E/liquid_nitrogen.html
Does anyhting look familiar?
The best part of Liquid Nitrogen Day was using a banana as a hammer.
Send me on a copy of the photo.
Dan W.
At 10:13 AM 2/13/02, you wrote:
>Artifact question:
>
>I have a lead bell (shaped like the Liberty bell) about 30mm in diameter
>at base and 25mm tall. It has an iron nail through the center. It is
>marked "Landreth / Phila / Trade Mark" I think that it is an insulator, but
>I am by no means certain. Does anyone have any info on this company or
>other lead bells? Context is late 19th century/early 20th century. I'll be
>glad to send a photo...
>
>Thanks,
>
>
>Carl Steen
>Archaeologist
>The Diachronic Research Foundation
>PO Box 50394
>Columbia, SC 29250
>Web Site: http://diachronicresearch.com
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