Some years ago, you could buy small tubes of calcium carbide called Bangsite at fireworks stands around 4th of July. It was used to make the gas to fire carbide cannons that were also sold at the fireworks stands.
I had one as a teenager (one of my least practical purchases). It had a small reservoir for a little water and a mechanism that would drop a little Bangsite into the water. After doing that and waiting a few seconds, you pushed a knob that struck a lighter flint against a steel file, producing sparks that lit the air/acetylene mixture in the chamber above the water. If the mixture was right, the cannon sounded like a 12 gauge shotgun going off. I got into a little trouble with that thing a couple of times!
The last time I went walking with my Uncle on what had been his farm, we looked through the junk pile. He pointed out the acetylene generator his father had used in the 20"s and early 30"s to do gas welding and cutting. Later my Uncle Bob tried using the generator and ended up having a small explosion that he said COULD have been the end of him. He decided that using gas cylinders was a whole lot safer than trying to use the old and maybe in poor shape acetylene generator. And they seldom gas welded any more, as they had REA electricity by the early 50"s and got a stick welder.
Bob showed me how the generator worked. It was more or less the same as my cannon, except on a much larger scale. A measured amount of calcium carbide dropped into water inside a closed chamber of about 10 gallons. If I remember right as the acetylene was produced by the reaction of the carbide and the water, you needed to bleed off the first amount to get rid of the oxygen in the chamber and then the acetylene would pressurized the chamber. If everything worked right, you had usable acetylene for a while. After the reaction was complete, there would be lime in the water that needed to be cleaned out.
Uncle Bob said I could have the acetylene generator if I wanted it, but I had to promise to never try to produce acetylene with it, since he thought it was just too dangerous. But I didn"t have a good way to haul the unit, and it had been sitting outside in the junk pile for 40 or 50 years, so I left it there.
I did think it was very interesting though. A way to produce acetylene gas on the farm.