[Gibbon1]

There is a chapter on acetylene lamps I read. There was maybe 50-75 years of development by different companies and inventors trying to solve a bunch of issues with a frankly simple device. Easy enough to build a lamp the slowly drips water on to calcium carbide and burns the acetylene, that works on the bench.

Now build one that will work reliably when the miner dropped it, cleaned and refiled with water from murky puddle, in the dark 500 feet below ground.