“From the barracks about 2 miles away, I inserted two wires, bare ends in the ground, about 50 feet apart.
I then stuck a 9 V battery to the other two ends.
He replied the needle just pegged on the chart recorder.”
Ok... So the “DC” current from the 9 V battery somehow activated a residual detectable “AC” current?
I am literally going to try this right after daylight...
No.
It offset the DC bias that was being used to center the AC signal in the center of the chart.