The Hyfrecator, made by the Birtcher Corp., was a small(shoe box sized)
electrosurgery unit. I have used them , in the past in my dental
practice. It was a spark gap type TC putting out about 2 KV.-at- a mixture
of frequencies. One terminal, called the indifferent terminal was placed
under the patient. It was a metal plate , square, about 5" on a side.
The hot terminal was a handpiece that held different shaped electrodes
and the patient was the toroid( no, there were no brush discharges from
their ears). There were two types of current available, dessication(
shrank and dried the tissues) and coagulation(stopped bleeding). A third
type called fulguration, dispensed with the indifferent terminal and
used a bipolar instrument, with a small spark gap that destroyed tissue
and left only a small carbonized mass behind.
     Larger hospital units added CW current which only cut, but by
blending the two currents you could, both cut and coagulate so there was
no bleeding.
    The Hyfrecator is no longer used, as it created massive amounts of
TVI, BCI and RFI.( I didn't have to tell you guys that, did I?)
                          73, Ira  W3ZLK