11. One was a processed bamboo fiber used for a filament inside a glass bulb containing a vacuum. 12. Over it curves the glass bulb , which condenses the mercury that is evaporated as the device operates. 13. Thus the glass bulbs are created. 14. Francis Hauksbee developed a more advanced electrostatic generator around 1704 using a glass bulb that had a vacuum. 15. The Gem was the company's first dimmable glass bulb and remains their best selling light bulb to date. 16. It consists of a large weighted glass bulb with a thin stem rising from the top with calibrated markings. 17. Unlike glass bulbs , LED's are hard to break and will glow continuously for more than 11 years before failing. 18. The starter is a small metal canister with an inert gas and two bimetallic contacts enclosed in a glass bulb . 19. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger borosilicate glass bulb . 20. LED lights, which are encased in solid plastic rather than a hollow glass bulb , may be molded into any shape.
