A gargoyle finds himself caught between a rock and a hard place in this Xanth adventure that "should delight Anthony's many fans" (Publishers Weekly).   As a gargoyle, Gary Gar has one job in Xanth: to protect the Swan Knee River from the pollution flowing in from Mundania. But more dirt plus less rain will crack any gargoyle's stony composure.   So Gary does what any good Xanthian would do: He seeks the help of the Good Magician. But payment for his service is high. Gary must find a philter for the water, while taking on human form to tutor a wild human child, with help from the surly Sorceress Iris, and--even though time is of the essence--taking Hiatus, a known troublemaker, along for the ride.   It won't be easy, especially when they're all transported back to the dawn of time. And if they can't figure out what's going on in the past, there may be no future for Xanth--come hell or high water . . .   "Ephemeral amusement for pun-struck Xanthonauts." --Kirkus Reviews