This is one of those friendly, might-be-true stories which almost comes through as another facet of eternal boy. A Newburyport background -- the real adventures of flesh and blood boyhood a generation ago -- mischief, pranks, good fun. But there is something a bit amateurish in the telling that keeps it from being as good as one thinks it is going to be. It lacks the laughter and tears of reality. But it is a good tale and matter of fact youngsters will like its sense of having happened.