Peter was right. The church was open, though not for religious services. Some one was playing upon the organ. As the boys entered, a swell of sound rushed forth to meet them. It seemed to bear them, one by one, into the shadows of the building. Louder and louder it grew until it became like the din and roar of some mighty tempest, or like the ocean surging upon the shore. In the midst of the tumult a tinkling bell was heard; another answered, then another, and the storm paused as if to listen. The bells grew bolder; they rang out loud and clear. Other deep toned bells joined in; they were tolling in solemn concert--ding, dong! ding, dong! The storm broke forth again with redoubled fury--gathering its distant thunder. The boys looked at each other, but did not speak. It was growing serious. What was that? _Who_ screamed? _What_ screamed--that terrible, musical scream? Was it man or demon? Or was it some monster shut up behind that carved brass frame--behind those great silver columns--some despairing monster begging, screaming for freedom? It was the Vox Humana! At last an answer came,--soft, tender, loving, like a mother's song. The storm grew silent; hidden birds sprang forth filling the air with glad, ecstatic music, rising higher and higher until the last faint note was lost in the distance. The Vox Humana was stilled; but in the glorious hymn of thanksgiving that now arose, one could almost hear the throbbing of a human heart. What did it mean? That man's imploring cry should in time be met with a deep content? That gratitude would give us freedom? To Peter and Ben it seemed that the angels were singing. Their eyes grew dim, and their souls dizzy with a strange joy. At last, as if borne upward by invisible hands, they were floating away on the music, all fatigue forgotten, and with no wish but to hear forever those beautiful sounds--when suddenly Van Holp's sleeve was pulled impatiently and a gruff voice beside him asked: "How long are you going to stay here, captain--blinking at the ceiling like a sick rabbit? It's high time we started." "Hush!" whispered Peter, only half aroused. "Come, man! Let's go," said Carl, giving the sleeve a second pull. Peter turned reluctantly; he would not detain the boys against their will. All but Ben were casting rather reproachful glances upon him. "Well, boys," he whispered, "we will go. Softly now." "That's the greatest thing I've seen or heard since I've been in Holland!" cried Ben, enthusiastically, as soon as they reached the open air. "It's glorious!" Ludwig and Carl laughed slyly at the English boy's _wartaal_, or gibberish; Jacob yawned; Peter gave Ben a look that made him instantly feel that he and Peter were not so very different after all, though one hailed from Holland and the other from England; and Lambert, the interpreter, responded with a brisk--