The Mazda type S-1 sunlamp was marketed during the 1930s as a “distinctly artificial sunlight source for ultraviolet health radiation”10. "When the lamp is turned on, the filament and electrodes glow brightly. In almost the same instant the mercury vaporizes and an arc stream flows in the gap between the electrodes. Not unlike the sun itself, a wide range of rays dart forth from this energy source. When they strike the special glass bulb, only the desirable rays are permitted to pass through.”12 This is the more common inside frosted version.