Diathermy is when high frequency currents are used to heat, cut, coagulate, and destroy tissues.  Diathermy Machines were used to lower blood pressure electrically before medications were available.  When used surgically, they were most beneficial in the removal of cancerous cysts.  Unlike the scalpel, where excessive bleeding occurred  (and re-infecting good tissues with bad cancer cells) electrical cutting of tissues allowed the blood vessels to be sealed as they were cut...cysts could be cooked in a sense before removed, and all in all the procedures had an overall success rate that was higher and with a speedier recovery.  Today they are replaced with lasers, and although they look straight out of Frankenstein were actually legitimate medical tools in the 1920s, even if occasionally they were pawned off by quacks ;) ...

Oudin Resonators were large Tesla Coils used to apply sparks to the skin and diffuse electricity to produce physiological effects on the body.

H. G. Fischer G2 Spark Gap Diathermy Machine, 1930s

Slicing instantaneously through 25mm of steak using a diathermy machine.  The meat was sliced 18mm deep using a a 1/2mm needle moving as fast as my hand could travel.

 Drawing sparks to a piece of metal held in the hand from a Oudin Resonator

Hot arcs from a gold diathermy electrode.  These arcs can instantly coagulate tissues.

Surgical diathermy machine made by A. S. Aloe

Dehydrating sparks from a glass vacuum electrode to dry the skin or sterilize the skin on the surface

A smaller portable A.S. Aloe Diathermy Machine removed from its case

Internal components including the Tesla Coil on the left

A. S. Aloe "Lightning" Machine  


Demonstrating electrocoagulation of the tonsils 




Gold-plated Diathermy Electrodes from H. G. Fischer

H.G. Fischer Type G/GP Diathermy Machine.  An industry standard in the 1920s.

Showing internal components including reactance coil, high voltage transformer, mica condensers, and Tesla Coil.

H. G. Fischer Type Y Diathermy Machine


H. G. Fischer Type H Diathermy Machine.  Consumes over 1KW.

Later Short Wave Diathermy Machine from the 1950s given to me by the H. G. Fischer family.

Internal components of SWDI Diathermy Machine from H. G. Fischer.  Unit operates around 30 MHz.


Internal components of 1950s Diathermy Machine from H. G. Fischer

An inexpensive 1940s Diathermy Machine made by Physician's Equipment Co.

After short wave Diathermy they experimented with ultrasonic diathermy.
Unpulsed as this machine generates and later they switched to pulse diathermy to avoid breaking down bone structure.


H.G. Fischer Magazines outlining Diathermy techniques.


Most manuals recommended practicing on steak before moving to patients...


Diathermy was commonly used for electro surgery in cases where excessive bleeding could occur with a scalpel.

It was often used to remove the tonsils.

Diathermy was also used to induce heat in tissues for rehabilitation.

It was used to treat skin cancer as well as for removing malignant growths surgically.

Diathermy was also used to treat the cervix and prostate.


Diagrams showing techniques for short wave diathermy.

Liebel Flarsheim Bovie machine for Diathermy, Coagulation or Electric Scalpel.
Originally designed for brain surgery. 

A larger version of the same machine.  This machine became a long standing surgical unit well into modern times.

Restoring a completely weather damaged Bovie Diathermy Machine.  Mejla (RIP) helped.

The unit was made perfectly functional again.

Liebel Flarsheim Short Wave Diathermy Machines

McIntosh Hogan electrosurgical machine and Oudin Resonator.

Frank drawing sparks off of the Hogan.

Hotter sparks from the Tesla terminal, a pancake Tesla Coil on the side of the machine.


Small Mcintosh Diathermy for minor surgical procedures

A frequency adjustable Diathermy Machine from McIntosh.

Thompson Plaster Electrosurgical Cabinet

Thompson Plaster machine as seen in Normal Rockwell art.

Io (RIP) loved her Thompson Plaster machine.

General Electric Diathermy Machine.

Wappler Excel Floor model Diathermy Machine.

Peerless Diathermy Machine

A series of pristine Diathermy Machines from David Genser (RIP) AKA Darkerwaters.
Dave was a great guy who did special effects for X-files and provided high voltage props for Alice Cooper concerts.
He also  blamed me for spending over $35K in machines after getting inspired from my website.

He restored machines to better-than-new condition, a painstaking process!

Diathermy as seen from Otis military photos.


Effluve from McIntosh Oudin Resonator to my hand.

Several Diathermy Machines I restored to have clear tops for educational purposes.



McIntosh Diathermy Machine having an adjustable frequency and a conical Tesla Coil.


Tesla Coil from Fischer G/GP Diathermy Machines

Tesla Coil from Dyne-Electron Diathermy Machine

Tesla Coil from Rose Diathermy Machine.  Primary Coils on top, secondary coil below.


Conical Coil designed byJeff Behary to resonate as a magnifying transmitter when wired to a Diathermy Machine.


Adjustable coagulation electrode showing how sparks can be limited to the pointed end electrode by intervening a spark gap in series with the output.

Glass condenser electrode used for heating the body internally or surface applications.
The glass electrodes were invented by Dr. Frederick Finch Strong in 1896.

Showing low frequency "hot cautery" also available with some models of Diathermy Machines.

Wireless lighting demonstrated with the McIntosh Hogan Oudin Resonator.

Diathermy Electrodes
for internal and external body parts.

My daughter Madeline demonstrating how to light a lamp with high voltage.

Astrid and I used a McIntosh Hogan machine to "carve" pumpkins electrically one year.

By passing electricity through her body to a metal wand she was able to ignite explosive gases that were introduced into the jack-o-lanterns.


Dr. Frederick Finch Strong and his wife Ethel.  Pioneers in this field.

The concept of the Oudin Resonator modified by Jeff Behary and engineered to make artificial lightning.
Note the lamps lighting without wires in the photo above.

The hot sparks used for surgery can also be extended to Tesla Coils for creating hot channels of lightning-like arcs.

For more information, visit the Electrotherapy Museum: