I was walking by a path not well traveled by my tractors. There lay a 40 cy ft gas cylinder. Just what I needed. May be a problem though. I kept it out of the iron pile, they don't seam to like cylinders that are closed, and it was marked with GS Parsons around the top. I was going to return it to them, but never did. Since I am the last survivor, I have no idea who drug it home. Now if I take it to a GS parsons dealer, I assume it will need to be hydro checked. If it passes, will they fill it with Argon/co2 regardless what was in it? . It has a valve, so I think it is clean. Any thought? Stan