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Although gas lamps started to spread from the early 1800s onwards, these early gas lights were open-flame burners that were not much brighter than torches or candles. The bright gas street lamps in which an incandescent mantle, rather than an open flame produces light and which are a bit dimmer than electric street lamps, though are adequate for modern street lighting, and remained operating in some historical city centers, were invented only in the 1880s, concurrently with the electric light bulb. Even the pressurized kerosene lamps like Coleman and Petromax, which produce much more light than an old-fashioned open-flame kerosene lantern were only invented in the 1910s.

Suppose that for whatever reason, the invention or the spread of electric lighting is delayed by some decades.
What technological advances do you think could have come in combustion-based lighting, either gas or kerosene lamps, that would have continued to increase their brightness and convenience of use?
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