i wondered about the cat hiding in the branches, and found this strangely parallel universe, where yggdrasil is not a tree, but an institute that researches uranium:
http://www.earthisland.org/yggdrasil/uep.html
now my question: is the salivation due to radiation damage in the soft tissues of the mouth, or is the cat ringing a bell in the treetops as the isotope decays?