Gasoline is very very very very very dangerous stuff. It is not a safe appropriate accelerant to start even the most stubborn fires. This is why when you buy charcoal starter fluid it contains naptha and or kerosene. Gasoline or petrol is far far far far far far too volitile to use as an accelerant, even you admit it's volitility took you by surprise and resulted in mild burns with only a cup full, or only the equivalent of ~5 thimbles full of it. You got lucky but no 'skill' protected you. When you pour out such a volitile flammable and dense chemical such as gasoline it always makes a low lying cloud of vapor because it evaporates so readily. It had nothing to do with the length of the gasoline trail either...