A Polish family in the Middle Ages guards a great secret treasure and a boy's memory of an earlier trumpeter of Krakow makes it possible for him to save his father
"One of the best stories he has written and an interesting picture of life in the days when printing was looked upon askance, when necromancy was only just becoming suspect, when the Spaniards hold terror over the heads of the Belgians -- and Plantin went on fearlessly daring the world to stop his printing press. A first rate adventure yarn, with a bit of romance -- and an authentic background. A book which should be valuable in its contribution to the story back of printing, as well as a good tale, well told." -- Kirkus Review, 1938