not so fast
One of the stories I read concerning peg lamps is that until the use of whale oil, candles were the main light source. A home had numerous candles and holders to light various rooms and areas. Women were not eager to part with their candleholders, and were reluctant to replace their candles with whale oil lamps. So the peg lamp was created. The peg fit snuggly into the candle-holder allowing the candleholder to continue to be used.
As you can see in the second photo, the glass vessel has a peg at the bottom, which conveniently fits into the metal candleholder. This option made it possible to continue to use the candleholder while using whale oil. In today’s world, if one did not want to burn oil in a peg lamp, wouldn’t this piece make a cute vase?