Left with their grandmother while their archeologist parents are on a dig, Tim and Nan pass the time by staking out the yard of the family homestead and digging for artifacts. The relics that emerge, however, are recent—like their deceased grandfather's favorite pipe. This inspires Tim to create a poem, which proves to have extraordinary power: saying it sends the children back in time to give their beloved grandfather a last hug. Other lost treasures allow them to help their parents elope; to visit a scene of political bigotry that divided their great- grandparents; and even to rescue their grandmother from a flood. After the grandmother dies and their parents return, their mother is able to go back with them to visit their great-grandmother, pregnant with the baby who became their grandmother—a special hello and goodbye. A powerful storyteller, Griffin here fulfills the promise of her first book, Otto from Otherwhere (1990). Although time-travel stories abound, few illustrate the continuity of place and family so well. The internal logic of the poetry and of the rules governing time travel are maintained; the hint of deeper meaning is reminiscent of Mahy. (Fiction. 10+)