Check Wikipedia for some interesting history of the RENULIFE VIOLET RAY machine.

And you can even buy a vintage model...

https://www.ebay.com/itm/Vintage-RenuLife-Model-2-Violet-Ray-Generator-Glass-Electrode-Kit/233753584730?hash=item366ccca45a:g:W9gAAOSwzjVfkKhF

And most interesting, the user manual of what treatments it performs. See page 5 for the list of 49 conditions it treats, including Baldness. But I can attest that it does not work for that.

http://www.violetwandstore.com/Articles/renulife_users_directions1919.pdf
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Stephen M