Every big tree has a spirit. Some trees house many spirits. Whether a tree is a spirit or is inhabited by a spirit is not an easy question. The people will say: The tree has a spirit, or: in the tree there is a spirit. The spirit has a voice which the careful listener can hear and even understand if he knows the language of the spirits. This voice has to be preserved carefully by the drum maker. The boat-maker too, wants to keep the spirit of the tree in the wood so that it will protect the boatman against drowning in the treacherous rivers, when the tree has become a boat. The appearance changes, the spirit remains. Together in a forest, the trees have a collective spirit, powerful enough to be revered as a god.