[quote][b]Posted by:[/b] burritosenior [quote][b]Posted by:[/b] Zealot of Law No, the blue flame is composed of the fuel that hasn't completely combusted, when it gets red it is fully combusted and at its hottest. [/quote]You've got your facts mixed up I do believe sir.[/quote]Aye. Red/yellow flames are fairly inefficient as a result of wasted fuel. Blue/white flames are hotter and more efficient. Flames only have colour as a result of impurities and so on. So, hydrogen burns clear, copper oxide in a flame will burn green and so on. As to how to do that fireball in the hand, it has nothing to do with the fuel in the flame. If something is hot enough to have a flame, it's hot enough to kill a human. Basically, spray your hand with deodorant (plenty of it, too little and it'll hurt), and then light it. If you do it right, it doesn't burn your hand. Nothing to do with the heat of the flames, simply that it's burning what's on it as opposed to your hand. Same way that candle wicks work, actually. Or, as a better example, the wicks in oil lamps. It burns the fuel, not the wick (which is also flammable). Also, no, the top bit of the flame isn't the hottest part, anyone who has ever used a Bunsen burner knows that the cone you can see is the hottest part. :) The top just makes a test tube black very quickly due to waste hydrocarbons produced from a butane fire. Oh, that video is [i]neat[/i]. Because you're not holding it near where the heat is (flames rise, after all), and your hands aren't covered in any fuel, you just end up with a fireball that you can hold quite comfortably while there's fuel in it. Neat trick, but nothing extraordinary. [Edited on 05.02.2009 11:32 PM PDT]