> , the USGS was conducting water table surveys
> > of deep wells in the area and placed a float and drum
> > recorder in one of the deep wells in the Nunn-Bush factory.
> > During the period of recording Uncle Elmer noticed that
> > certain anomalous squiggles on their recordings corresponded
> > to major seismic events that had made the news at the time.

About 5 years ago, I made contact with a person in the Santa Barbara
area who had been running a similar
recorder for some time.  It was written up in the local paper, and a
couple of us went to see the unit.
It was a float with a weight on the bottom, and a very small rod on the
top.  It floated in a pool of water
in a hole in his yard.  A magnet on the top generated a signal in a
coil.  As I remember it was held in the
center by threads to the sides.

The output was to a drum recorder which he had constructed.  The unit
seemed to have good sensitivity
to both local (he was not too far from a railroad track), and distant
events.

George Harris

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