Grease and oil are hydrophobic - which means that in layman's terms they don't like water. They don't mix. So when you put water on a grease/oil fire the oil tends to stick to the surface of the water. The water then spreads the fire just like a river carrier sticks to the sea.
Likewise, can water increase fire?
Water can actually do three things with fire: Feed it, not affect it, or quench it, depending on the fuel. For burning solids, such as paper, wood, or coal, water will extinguish the fire by two methods: cooling and, if enough is present, depriving the fire of oxygen. A fire needs three things: heat, fuel, and oxygen.
What can you put in a fire to make it bigger?
Then it takes more heat energy to trigger the reaction with oxygen. The amount of heat produced depends on the molecules that make up the fuel. A twig catches fire easily because it heats up easily. Surface area: The bigger the area of the surface of the fuel, the more oxygen molecules can collide with the surface.
Can you catch water on fire?
Burning springs are natural seeps of methane that can catch fire, but they come from underground rock layers. Regardless, Baumgardner's comments that “Indians” lit the water on fire are hardly comforting, especially when you're not expecting your tap water to burst into flames.