Tube Time on Twitter: "here's a light bulb that is almost 120 years old! the filament is made out of carbon, and the glass is clear because they hadn't figured out how
All About Carbon Filament Bulbs - Lighting Illusions Online
Carbon Filaments vs Tungsten Filaments - YouTube
Lighting Supply Blog: A Little Light Reading - LIGHTING SUPPLY
Carbon filament lamp hi-res stock photography and images - Alamy