Fireproof Paper

The paper is thin enough that the heat from the flame is very efficiently drawn away by the water in the cup. You can actually boil water this way.

However, once enough of the water boils off, watch out! :-)

It is an old scoutmaster campfire trick. Ask the scouts what happens when the paper cup full of water is placed on the campfire. We all guessed that the wax would melt or the paper will burn. I remember watching the water boil in that paper cup as a young camper.

Water boils at (and will not get any hotter than) 100ºC; paper needs to get a lot hotter to burn.

Thanks for clearing that up for me.

P.S. I love the new format!

Same for a boat burning to the waterline...I think. But then again I think I've read accounts where the boat "burned to the waterline and sank".

Having burned to the waterline, all it takes is a small disturbance and water comes aboard... which lowers the boat ever so slightly... making it fill very quickly with water, and down it goes (a very quick vicious cycle). (A boat with no freeboard is hardly a boat.)

Boiling Point of water: 373.15 K, 100° C; 212° F

The cup won't burn until all the water is gone. The water won't go unless it boils or leaks/evaporates away. As long as the flame not so hot as to boil the water it will never burn the paper.