In Rutherford's 1913 text, "Radioactive Substances and their Radiations",
page 625 describes a procedure for extracting a radioactive source from
the atmosphere by exposing a wire to air for several hours, while keeping
the wire at several hundred volts negative. The daughter products of
radon isotopes are collected on the wire:
"...In order to multiply the effect, a wire about 20 metres in
length was exposed at some height from the ground, and was kept charged
to a high potential by connecting it to the negative terminal of an
influence machine..."
My question to the List is this: What is an "influence machine"?
My guess is that it an X-ray machine. Any thoughts on this??