Jacques Aubry shrugged his shoulders, but as he did so he determined to solve the mystery. It was the easiest thing in the world for one who, like himself, went in and out of the house as familiarly as if he were one of the family. He made up his mind, therefore, that he would go and see Gervaise the next day, but that on this evening he would remain at the Grand-Nesle until ten o'clock; at ten o'clock he would say good night to everybody and pretend to go away, but that he would remain within the precincts, climb a poplar, and make the acquaintance of the phantom from a hiding place among the branches. Everything fell out as the student planned. He left the studio alone as usual, shut the door leading into the quay with a great noise to indicate that he had gone out, then ran rapidly to the foot of the poplar, seized the lowest branch, drew himself up to it by his wrists, and in an instant was at the top of the tree. There he was just on a level with the head of the statue, and overlooked both the Grand and Petit-Nesle, so that nothing could take place in the courtyard or garden of either unseen by him. While Jacques Aubry was taking up his position on his lofty perch, a grand soirée was in progress at the Louvre, and all the windows were ablaze with light. Charles V. had finally decided to leave Fontainebleau, and venture within the walls of the capital, and the two sovereigns had entered Paris that same evening. A gorgeous welcoming fête awaited the Emperor there. There was a banquet, gaming, and a ball. Gondolas lighted by colored lanterns glided up and down the Seine, laden with musicians, and made melodious pauses in front of the famous balcony, from which, thirty years later, Charles IX. was to fire upon his people, while boats gayly decked with flowers conveyed from one bank of the river to the other those guests who were on their way from the Faubourg Saint-Germain to the Louvre, or who were returning to the Faubourg Saint-Germain. Among the guests the Vicomte de Marmagne was naturally included. As we have said, the Vicomte de Marmagne, a tall, pink-cheeked, insipid dandy, claimed to be a great destroyer of hearts. On this occasion he thought that a certain pretty little countess, whose husband happened to be with the army in Savoy, cast meaning glances at him; thereupon he danced with her, and fancied that her hand was not insensible to the pressure he ventured to bestow upon it. And so, when he saw the fair object of his thoughts leave the ball-room, he imagined, from the glance she gave him as she departed, that, like Galatea, she was flying toward the willows in the hope of being pursued. Marmagne therefore set out in pursuit, and as she lived in the vicinity of Rue Hautefeuille his course lay from the Louvre to the Tour de Nesle, and thence along the quay and through Rue des Grands Augustins to Rue Saint-André. He was walking along the quay when he heard steps behind him.