The luck of the Irish apparently eluded young Patrick O'Michael O'Sullivan O'Callahan. The only leprechaun he could catch was as poor and hungry as Patrick. Instead of transforming the dandelion soup to a pot of gold, Tippery comes up with a bowl of frogs. But his next effort is not in vain. Though the rocks in the fields do not become golden nuggets, they wield their own kind of magic on Ireland -- for Tippery is responsible for the first batch of spuds ever known in the land. Roger Duvoisin is as refreshing in the Caeilc as he is in the Gallic and Mary Calhoun's story makes ideal if delayed St. Patrick's Day reading in school and home libraries.