Completely and totally off-topic and without any merit

From: Joe R. <>
Date: Fri Sep 10 09:01:54 2004

At 09:40 PM 9/7/04 -0400, William Donzelli wrote:
>> Telescope makers use it to make small "pin holes" in photo graphic
>> plates and film. You smash some and it makes hundreds of tiny specs
>> that are almost perfectly spherical. These cast shadows on the the
>> photo material. The film that is exposed turns dark, leaving the
>> tiny clear spots. One simple mask off the ones that are not used.
>One interesting place mercury is used is in near-frictionless
>bearings. Gyrocompasses from World War 2 <snip>

   That reminds me, submarines used to (or still?) use mercury as ballast.
They used mercury since it could be pumped fore and aft or side to side to
get the proper balance. I know a guy that bought on old sub for scrap and
it contained something like 5,000 or 10,000 pounds of mercury and a HUGE
amount of lead (in the lead acid batteries). He bought the boat for
something like $1000 and sold it for about $115,000!!

Received on Fri Sep 10 2004 - 09:01:54 BST

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