Paul Devereux wrote an interesting article for Fortean Times about archaeoacoustics, listening for the sound phenomena associated with some prehistoric rock art and ancient spiritual sites:
Canadian rock art interested us because of a traditional Algonkian Indian belief that manitous – spirits – lived inside rocks and cliff-faces, and that shamans in trance could enter the rock surfaces and meet with them in order to exchange tobacco offerings for supernatural power, usually referred to as "rock medicine". (If the shaman failed to carry out this operation correctly, though, it was said he could become trapped in the cliff or rock he had spiritually entered and never return to his body outside. In our terms, he would die or go mad.) We wanted to test the hypothesis that such rock art marked venerated, magical places where the spirits could be heard; perhaps places where echoes were unusually strong. Had the Indians, like the ancient Greeks, believed echoes to be the sound of spirits calling, mimicking human-made noises to do so.
