But while she spoke to us in her sweet, clear voice, I stopped looking at the objects around us to look at the people. Arthur Rance was gazing at Mme. Darzac, when my eyes fell upon them, and Rouletabille seemed to be lost in thought, and far, far away from us all. M. Darzac and M. Stangerson were talking in low tones. The same thought was filling the minds of each one of these people--both those who kept silence and those who, if they spoke, were careful to say nothing which could give a clue to the thoughts. We reached the postern. “This is what we call the Gardener’s Tower,” said Edith, childishly. “From this gate one may see all the fort, and all the castle, both north and south. See!” And she stretched her arms wide to emphasize her words. “Every stone has its history. I’ll tell them to you some day, if you are good.” “How gay Edith is!” murmured her husband. I thought to myself that she was the only one who was gay in the party. We had passed through the postern and found ourselves in another court. Opposite us was the old donjon. Its appearance was more than impressive. It was high and square, and it was on account of its shape that it was known as the Square Tower. And, as this tower occupies the most important corner of the fortification, it was also known as the Corner Tower. It was the most extraordinary and the most important part of this agglomeration of defensive works. The walls were heavier and higher than those anywhere else, and half way up they were still sealed with the Roman cement with which Cæsar’s own columns had welded together the stones. “That tower yonder, in the opposite corner,” went on Edith, “is the Tower of Charles the Bold, so called because he was the Duke who furnished the plans when it became necessary to transform the defenses of the château, so as to make them resist the attacks of the artillery. Don’t you think I am very learned? Old Bob has made this tower his study. It is too bad, for we might have a magnificent dining hall there. But I have never been able to refuse old Bob anything he wanted. Old Bob,” she added, with a charming smile, “is my uncle--that is the name he taught me to call him by when I was a little thing. He is not here just now. He went to Paris on the five o’clock train, but he will be back to-morrow. He is going to compare some of the anatomical specimens which he found at Rochers Rouges with those in the Museum of Natural History in Paris. Ah--here is an oubliette!” And she showed us in the centre part of the second court a small shaft, which she called, romantically, an oubliette, and above which a eucalyptus tree, with its white blossoms and its leafless limbs, leaned like a woman over a fountain.