These were sold by Standard Oil up until the 1950's, and were listed in the 1908 Sears Roebuck catalog for $2. Millions were made and they turn up on dusty thrift store shelves with surprising regularity once you get the knack of spotting them. Not the most efficient lamp on the market, but with 40 watt light output from a tough, easily managed, silent, kerosene lamp, it fills a gap. It also produces a good deal of heat along with light when that's a concern, and ventilation is adequate. That's my first Rayo with the green shade. This one I found today for $15. Somebody bent the shade holder in for a shade with an 8" fitter, but that's clearly adjustable. The centerdraft design breathes well, and the flame spreader, with the latest patent in 1905 needs no improvement. Match light, no preheat, no fragile mantle, parts are still available online. If the fuel cap sticks, and they all seem to, just remove the burner and pour fuel down into the fount. I suspect lots were fueled this way, with a steady hand and no funnel. Add citronella to kerosene to make light and keep bugs away. Everything you ever wanted to know about Rayo lamps is in Book 4: Kerosene lamps, by Ron Brown.
I love the center draft lamps....much better light (and heat) output than single and dual wick models. I pieced together a Manhattan student lamp for low light needs, have a couple Rayo for intermediate, and a Rochester store lamp if I really need bright light. Also some Aladdins if I feel like messing with mantles although I do have an electric insert for them.
Good in between lamp. Need lower light safer lantern for barn and walking, metal with bail handle, Rayo or hole in center for general purpose light, brighter than a straight wick, but still not fussy and easy to take care of, Colman or Aladin for bright light, super bright, super hot, delicate, take quite of bit of fussing with until you get it down, and not cheap. In the short run, I have went 100 % to LED's with rechargeable batteries, use either solar or ac to charge, have about 6 of straight line mantels, one Aladin, a couple of barn lanterns and a couple of circular wick ones. Would be excellent trading goods and it is so da** hard to ignore one full of sludge at a yard sale in perfect condition and 100 years old with a 50 c price tag on it. Have canned kerosine that is 30 years old open now and using, just as clean as day I bought it and bottled parafin type lamp oil that is still in bottle that is 20 or 30 years old that seems to be just as good as the day I bought it. If I was 100 % sure that TSHTF was about to happen I would buy a couple of 55 gal drums of kero or maybe 275 gal tank of it. Heat, cooking, light, storage, it is good in all those areas.
I read Ron Brown's chapter on the Rayo again and noted something that I'd missed, but should have known. Being an unpressurized wick lamp the Rayo will run on mineral spirits, charcoal lighter fluid, and even diesel fuel, or a mix of these fuels. Less volatile fuels would lower light output, but add versatility.
Should run on anything that'll burn, but doesn't have too high a flash point (like white gas or gasoline). I think denatured alcohol would run just fine, but I'm sure the light output would be less than with kerosene, and would wonder about fuel consumption. Sounds like an experiment.
