The Mystery of the Flame Juggler

Cornmarket is one of the busiest streets in Oxford, and I walk down it often, because it's pedestrian only and leads to various of my favorite haunts, like Marks & Spencer. Along the way, I'm lucky to have not only a whole lot of people watching to do, but also a soundtrack, because the street is lined with buskers ranging from a guy playing a ragtime song on his guitar to a young opera singer to a pair of young men playing some really enchanting but hard to place music on the cello.

And then there is the flame juggler. He's almost always there when I pass along the street, tossing and catching three flaming torches. Or at least they look like flaming torches. The question that's been plaguing me is: is the fire real?

Evidence in support of the real fire theory:
1. He sets out a rope to create a 2 meter boundary around himself so that people don't get too close.
2. His face and hands are sooty.
3. The flames look real enough.

Evidence against the real fire theory:
1. He could be doing the boundary thing and making his face sooty just to make us think it's real.
2. The flames don't seem to give off any smoke, either visible or smellable.
3. It would be crazy dangerous if he were using real fire.

So the chances are about 50-50 right now. Clearly, I need to deepen my investigation, for example by observing him when it starts raining or when he ignites and/or quenches the flames. I'll let you know if I ever figure it out.