Schumann Resonance today.. shows the Violet Ray in Lowest Amplitudes.. the highest visible light in our Vision is the Healing Ray developed by Tesla. The early electrical healing devices went under several names, but
were generally called “high frequency oscillators.” The Dental Brief
first used the term “violet ray” in 1913. In 1916 the first inexpen-
sive hand-held devices appeared in drug stores. The public accepted
the violet ray and hundreds of thousands of units were sold. Twelve
companies made the devices in the United States, Germany, France,
Spain, England and Canada.