"It is a Greek organ that was recently sent to Charles by the Emperor of Constantinople. The instrument is truly marvelous. With the aid of brass vessels and of bellows made of ox-hides, which are concealed from view, the air enters these tubes, and, when they are played upon, one time you think you hear the rumbling of thunder, another time, the gentle notes of the lyre or of cymbals. But look yonder, near that large table of massive gold where the city of Constantinople is drawn in relief, there you see no less ingenious an object. It is a Persian clock, sent to the Emperor only four years ago by Abdhallah, the King of Persia." Saying this, Octave pointed out to the young Breton and his grandfather, who became no less interested than Vortigern himself, a large time-piece of gilt bronze. Figures denoting the twelve hours surrounded the dial, which was placed in the centre of a miniature palace made of bronze, and likewise gilt. Twelve gates built in arcades were seen at the foot of the monumental imitation. "When the hour strikes," Octave explained to the Bretons, "a certain number of brass balls, equal in number to the hour, drop upon a little cymbal. At the same moment, these gates fly open, as many of them as the corresponding hour, and out of each a cavalier, armed with lance and shield, rides forth. If it strikes one, two or three o'clock, one, two or three gates open, the cavaliers ride out, salute with their lances, return within, and the gates close upon them." "This is truly a marvelous contrivance!" exclaimed Amael. "And are the names of the men known who fashioned these prodigies around us, these magnificent paintings, that gold table where a whole city is reproduced in relief, this organ, this clock, in short, all these marvels! Surely their authors must have been glorified!" "By Bacchus, Amael, your question is droll," answered Octave smiling. "Who cares for the names of the obscure slaves who have produced these articles?" "But the names of Clovis, of Brunhild, of Clotaire, of Charles Martel will survive the ages!" murmured the centenarian bitterly to himself, while the young Roman remarked to Vortigern: "Let us hurry; the Emperor is waiting for us. It will take whole days, months and years to admire in detail the treasures that this palace is full of. It is the favorite resort of the Emperor. And yet, as much as his residence at Aix-la-Chapelle, he loves his old castle of Heristal, the cradle of his mighty stock of mayors of the palace, where he has heaped miracles of art." CHAPTER IV. CHARLEMAGNE.