It is a carbide, acetylene gas, generator. This is different from the one I used. There was a water tank with a valve that allowed drops of water to land on a carbide cake. The cake looked about like those hard rice discs sold in food stores now. Once the carbide reacted with the water, the gas would start forming. The reason for the big funnel shaped piece is, it was floating in a tank underneath, floating on water, which acted as a seal to keep the gas in. The upper part, the funnel had a pointer on it, so you could tell by the scale how much gas it contained. On this one on the side you notice a pipe, with hose connection, and a regulator gauge. The whole thing sat on a steel wheeled cart, with an oxygen bottle strapped to it. To move it we shut it down, and carefully pulled it to where it was needed next, waited about 15 minutes for any sloshing to subside, before relighting the torch. If the tank ran out of water, the gas could escape, and possibly cause an explosion. When homes had gas lights, these were installed on the back porch, or in the wash house out back, eventually town regulations had them at least 100 feet from the house. The carbide was almost as corrosive as battery acid, would clog things, so it required a thorough cleaning a couple of times a year. On this one I think the cake is introduced thru that bale lid on top, not sure how the water was put in. Snapped this at a large auction some years ago. On the practical side, today, not so much, but think back to the days when everthing went by rail. Acetylene was and still is dangerous stuff, so was much more cost effective to ship those dry cakes in a box.
