I got another email from my Geophone FAQ. Again, I can't really answer
the question. I'd appreciate any thoughts for the reply and the FAQ. I
asked the author to join the list, but I don't think that happened yet?


I have a pair made of brass top and bottom
plates seperated by what looks like an iron
section. Ther are about 3 1/2" in diameter
and 1 3/16" thick ( each section being 3/8").

They are marked "GEOPHONE Joseph G Pollard
Co. New Hyde Park, N.Y. 1863".

My questions are :

1. Could they really be that old?

2. If they are, what were their uses during
that period ? 


I've seen the antique Chinese "instrument" with the balls that fall out
of the dragon mouths, but how far back does something like this go? I
know that there have been some large earthquakes "recorded" throughout
history, but I thought that most of the really old ones are estimated by
damages and people's guesses.

The list has been a little quiet lately hasn't it?

As always, thanks for responses,
Greg

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