In those days the _contre-danse_ had not hardened itself into the quadrille. It was danced, not in fours, but in sets of varying numbers, and of characters and figures mostly undefined. In one of the great halls, recently erected by the Emperor-architect, Charles VI., in a different taste from the older rooms, with marble floors and ceiling, and lined with mirrors, a very large set, composed of guests of the highest rank, was being watched by no inconsiderable number of their companions. It is difficult to conceive a more magnificent or fascinating sight, reflected and multiplied as it was by the mirrors on the walls. The Princess von Isenberg-Wertheim was dancing with a young noble, a prince of the House of Colleredo, a very handsome, but gay and reckless, young man. The dance was drawing to a close, the musicians, playing one of the last figures, _La Pastorelle_, to a very delicate and fine movement, to which the dancers were devoting their utmost, closest attention and skill. As the Princess was standing by her partner, awaiting their turn to go down the dance, a slight movement caused her to turn her head, and she found the Count, her friend, standing close to her. "I am sorry to interrupt, Princess," he said, in a low voice, "but I fear something serious has happened to the Prince. He cannot be found." The Princess turned very pale. She caught her breath for a moment, then she said, in the same tone, "Where is Karl, the _Jager_?" "I do not know," replied the Count. "I never thought of him." "Then he is not here," said the Princess, with a relieved air. "If Karl is with him the Prince is safe." The Count made a very slight movement of his shoulders, but the Princess turned serenely to the young man. "We will finish the figure, Monseigneur," she said graciously; "then, perhaps, you will excuse me." "Nothing has happened to the Prince, believe me," said the young man kindly, as they moved down the room. "He has doubtless gone on some private expedition with his servant. He probably forgot to leave a message, and will return to-morrow." The Princess was so reassured, apparently, by these reflections that she remained for the final figure of the dance. Then she left the palace, and, declining the Count's company, drove to her _Hôtel_ alone. She was more strangely moved than she could have explained to herself. She was, indeed, frightened and perplexed by her own feelings. She felt herself influenced by an hitherto unrecognised power, and, as it were, driven onwards by an overpowering impulse, not her own. Returning, as she did, at an unexpected hour, her women were not in waiting for her, and, leaving the servants who had accompanied her from the palace in the hall of the _Hôtel_, she wandered up the great staircase alone. The corridors and rooms were dimly lighted, and a perfect stillness reigned through the house.