Can you break the window with an egg?

Everybody knows that it is really impossible break the window with crude egg from short distance. So you can make a bet with your friends. First bet is won. New betters are coming. Lot off eggs are used but without success, without breaking the window. Only one can break the window – that one who knows that the window has to be hit by the tip of egg. And also, the window has to be well settled in the frame.