I’m not sure about that particular natural-gas furnace, but somebody recently posted these pictures of a giant fiery pit in Turkmenistan (although there’s a completely separate series of pictures of some kind of sinkhole tacked on at the end) which reminded me of the whole Shadrach, Meshach, and Abednego story.
I don’t buy it: Both natural gas (predominantly methane) and its combustion products are odorless. What most civilized folks think of as “the smell of natural gas” is an additive added by the gas company for exactly this purpose, so that people will be able to recognize gas leaks. But it wouldn’t be present coming directly out of the ground.
As to Shadrach et al’s furnace, wasn’t that rather explicitly something which Nebuchadnezzar ordered built, not something he just found already existing?
Not necessarily, but it might be similar enough to warrant a mention in a non-technical writeup such as this. I expect they actually mean not much more than ‘something is burning and you can smell it for miles’.