Can an improvised torch be made to last for a prolonged period of time? In the movie First Blood, there is a scene where Rambo is trapped in a cave after escaping a bazooka rocket that caused the mine he was hiding in to collapse. After realizing the entrance has been blocked, he decides to head down into the cave, and using the fire he built, a branch and some cloth he has, he prepares a torch (I can't remember now if he dips the cloth in some flammable liquid or not). Then he wanders through the cave for some time until he finds his way out, and the torch is holding up rather nicely... (he is seen feeding it with more strips of cloth from time to time)

My question is: is it realistic? Can a torch made from a branch and a burning cloth (whether or not dipped in gasoline or something else) be used for a prolonged period of time while remaining useful (i.e. not being burned-down, too hot to handle, etc.)?
The key is whether or not he added some kind of fuel to the cloth. Without that, a flammable cloth would burn itself out very quickly. If he had kerosene or some other fuel to soak the cloth, then the cloth would act somewhat like a wick in an oil lamp (except that it would not be "wicking" fuel up from any fuel source) in that mostly the fuel would burn rather than the cloth.  

If he had a liquid fuel source, even a non-flammable cloth like his clothing would have been made of would have sufficed. In fact, he probably wouldn't have had to keep adding cloth in that case, but he would have had to add more fuel periodically.  

So, the bottom line answer is: Without a liquid fuel source to soak the cloth, no chance. With a liquid fuel source to soak the cloth, no problem.