Jim, a young dog who is ""all alone in the world,"" misses the days when he lived with. . . a human family? his mother? no, his father, who went off one day on the trail of a delicious smell and never returned. Now there is only a lonely smell in the air, so Jim sets off on his father's trail--which takes him into a deep wood (""I never knew there were so many smells in the world,"" says Jim) and then, when he's chased by a bear, into the river. Jim grabs a log and drifts on it to an island. . . and guess who's there, moaning about being shipwrecked and separated from his son? A ""wiggling, waggling, prancing, dancing"" reconciliation follows, and then ""As the two dogs sailed out [on Jim's log] into the world toward new adventures, they lifted their noses to the night, and. . . made beautiful music together."" Bornstein does a fair job of simulating the tone that disarms in William Steig's animal stories, but the poetry is missing. And, as a father is neither the actual companion of a young dog nor the ideal end of an archetypal journey forth, so are the underpinnings. Sentimental.