Evoking eternity fire circle

In Evoking Eternity EA mentions making a circle impression to have a fire circle. He suggest using petroleum and styrofoam. Has anyone done this? Is he referring to gasoline?

Its page 76 if anyone wants ti check it out.

It’s a rudimentary sterno/napalm.

Easier to work with is gasoline, dishwasher detergeant and a bit of sawdust. You can mix it in the dishwasher soap bottle and squeeze it like a ketchup container. good for drawing, too.