>> in a surprising discovery, gas chromatography of the residue inside the heater's fuel tank identified gasoline and not kerosene. it takes more heat to ignite kerosene. gasoline ignites at very low temperatures. >> the difference in flammability between gasoline and kerosene is tremendous. and i worked in a lot of fires where people misfuel kerosene heaters with gasoline and end up having big fires. >> jean said they were using the heater outside before they moved it indoors. since a gallon of gasoline is equivalent to 20 sticks of dynamite, when jim poured it into the hot fuel tank, it caused an explosion, just as jean described. >> the residue of gasoline inside that smudge pot was the physical evidence. and mrs. long's story was the eyewitness evidence. it fits together.