According to Wikipedia:
Aerolux gas discharge light bulbs contained low pressure gas, either neon or argon, or a mixture of the two. Also within the bulb were metal sculptures coated with phosphors. These phosphors fluoresced when excited by glow discharge.
Aerolux gas discharge light bulbs contained low pressure gas, either neon or argon, or a mixture of the two. Also within the bulb were metal sculptures coated with phosphors. These phosphors fluoresced when excited by glow discharge.