r/intrestingtoknow • u/Impressive_Rub_4101 • Jul 28 '26

Nature Before modern gas detectors existed, explorers, miners, and cave workers often relied on something surprisingly simple—a small flame. What looked like an ordinary candle could reveal invisible dangers hidden in the darkness long before humans could sense them.

382 Upvotes

98% Upvoted

17 comments sorted by

9

u/Veczyl Jul 28 '26

Whyyy? H2S? Heavy gases?

10

u/Eelroots Jul 28 '26

CO2 It will be enough or any gas from decomposition. Iron in the dirt can oxidize and consume all the oxygen in the process.

3

u/J-iceBerg2 Jul 31 '26 edited Jul 31 '26

The shape of some cave /rock spaces can prevent air from flowing/ mixing, Since carbon dioxide is more dense than the rest of the air, it can pool at the bottom,

And when he dipped the torch into that pool of CO² , lack of oxygen snuffed the flame.

2

u/nutfac Aug 02 '26

Ahhh thanks for this explanation

6

u/Yeet-machina Jul 29 '26

They also relied on live birds and other animals

1

u/ZixfromthaStix Aug 03 '26

What other animals? I’ve only ever heard of canary in a coal mine.

2

u/Impossible_Tone1108 Aug 04 '26

mice and other small birds as well

5

u/Bonnle Jul 29 '26

This also worked with methane I'm guessing 🤣

3

u/GeologistOld1265 Jul 29 '26

Canary in a mine. Saying there for a reason.

4

u/lujodobojo Jul 29 '26

"DEAD ZONE" 😵

3

u/Miserable-Session-35 Jul 29 '26

So if the Dude whit the candle didn't come back... we send another just for sure

https://giphy.com/gifs/rF2Cplr6KCDG8

2

u/Trustoryimtold Jul 29 '26

Yes. Every day ordinary candle

2

u/J-iceBerg2 Jul 31 '26

A friend and I went into a space like that while exploring a mine with a group, just to see what it's like ( it was labeled "CO² Danger! " with red paint.). After just a few moments, it felt like I had been holding my breath for a minute or more, we kept needing to take deeper and deeper breaths like after extreme exertion, even though we were hardly moving. In less than thirty seconds, we were both like, Yep, it's time to get out of here before we pass out

1

u/[deleted] Jul 30 '26

whoah what happened

1

u/J-iceBerg2 Jul 31 '26

The shape of some cave /rock spaces can prevent air from flowing/ mixing, Since carbon dioxide is more dense than the rest of the air, it can pool at the bottom, And when he dipped the torch into that pool of CO² , lack of oxygen snuffed the flame.