Ten or so years ago I had the privilege of using a cesium proton
magnetometer on a historic site in Saratoga Springs, NY. The EPA
required an archaeology survey of the Superfund Priority Site, a
former "city gas" production facility across from "Red Spring #1" on
Excelsior Ave. on and under an active Niagara-Mohawk work/office yard.
The company I worked for was sub-contracted be another company looking
at contamination of the Groton, CT Navy sub properties, currently in
the news to be "closed". A large water control feature ran under the
"gas light" production facility emptying storm water into the nearby
lake. The idea, despite the large current natural gas line under the
facility, was to try to document the extent of the remains there
without disturbing the active facility.

The cesium proton magnetometer had a harness which held a small flip
top computer running MS software, a car "starter switch" to take the
readings (came also with software to sort out the up one line down
another sequencing, could also be used in "timer" mode taking readings
as one walked across various landscapes) and was the size of a small
beverage can on the end of a short light aluminum rod, very efficient.
Just before I was exposed to this (103 one summer day) it, I saw what
I think may have been the same equipment being used by Australian
archaeologists in Southeast Asia tracking down the origin of the
"celadon" ceramic story, partly deduced from underwater archeology
research. It sound whole acres I think of kilns buried beneath about 2
meters I think of alluvium, which they found with the magnetometer, as
firing earths creates magnetic anomalies. We used it to find the
former "gasholder" base (it's twin still stood and eventually was
placed on the US "National Register of Historic Places") and the
various maps and photos were "ground truthed" from the survey, and
shown to be still extant, in ruins, one brick "ring" the concrete
block office building was cracking over (nearby fault line also,
divides the Taconic from the Adirondack regions) as the site settled.
It has almost all the stages of gas/electric production on site, too.

However, I can't recall who made it. It came in a white "photon
torpedo" looking case (aka "Star Trek") via parcel post, and was
repaired once while we used it quite quickly. Any Aussie's know the
thing's name?

George Myers, Jr.
Many shovel tests later...