The Cascade Range, where it crosses the Columbia River, exhibits enormous cross sections of lava, and at its base are petrified trunks of trees, which have been covered and hidden from view except where the wash of the mighty stream has exposed them. Indians have told me, of their knowledge, that, buried deep under the outpours of basalt, or volcanic tufa, are bones of animals of siah , or the long ago.

Traditions of the great landslide at the Cascades are many, but vary little in form. According to one account, the mountain tops fell together and formed a kind of arch, under which flowed, until the overhanging rocks finally fell into the stream and made a dam, or gorge. As the rock is columnar Basalt, very friable and easily disintegrated, that was not impossible, and the landscape suggests some such giant avalanche. The submerged trees are plainly visible near this locality. Animal remains I have not seen, but these Salmon-eating Indians have lived on the river’s borders through countless ages, and know every feature in their surroundings by constant association for generations, and naturally ally these facts with their religious theories. (MacMurray MS.)

An excerpt from ‘The Ghost Dance Religion and Wounded Knee’, by James Mooney, Chapter VII, Smohalla and his Doctrine