"That protects the village in time of rainstorms," replied the tutor. "The soil here is of such a nature that it easily washes away, and if the town were unprotected the earth would soon be swept from beneath the houses. If you will look sharply, you will see outside the wall a deep trench which carries off the rushing water." As they were slowly riding along a road which wound around and over a high hill Yung Pak still kept his eyes wide open for strange sights. Suddenly he lifted his arm, and, pointing toward a tree upon a little hill at one side of the road, he said to Wang Ken: "Oh, what a queer-looking tree that is! And are not those strange leaves on it? What kind of a tree is it, anyway?" "Ha, ha!" laughed Wang Ken, "I don't wonder that you call that a strange-looking tree. Let's take a walk up to it and get a closer view." So the ponies were halted, and down sprang Yung Pak and Wang Ken. Leaving the ponies in charge of the _mapus_, they marched up the hill to get a nearer sight of the tree. "Why," said the boy, as they approached it, "those are not leaves that we saw from the road, but they are rags and strips of cloth. It looks as if some one had hung out their clothes to dry and forgotten to take them in again. What does it all mean?" "That tree, my boy," Wang Ken replied, "is called the sacred devil-tree. That is a queer combination of names, but you know there are a lot of ignorant people in our country who are very superstitious. They believe in all sorts of evil and good spirits. They think these spirits watch every act of their lives. Consequently they do all they can to please the good spirits and to drive away the evil ones. This tree they believe has power to keep off the bad spirits, so every man who thinks that a demon has possession of him tears a piece of cloth from his garment and carefully ties it to a branch. That is how all these strips you see come to be hanging above you. Some have hung there so long that the wind and rain have torn them to rags." "Yes, but why is this done?" asked Yung Pak. "Because," was the reply, "a man who is possessed by an evil spirit thinks that by thus tying a part of his clothing to the tree he may induce the spirit to attach himself to it instead of to his own person." Yung Pak's curiosity satisfied, they returned to the road, mounted their ponies, and quickly caught up with the rest of the party.