Wrapped in his cloak he kept the Emperor silent company during his studies, till the close of the first hour after midnight. The sharp, north wind which blew through the darkness did his aching head good, and still he racked his wits for some pretext to attract Hadrian from his labors, but in vain. His tormented brain was like a dried-up well; bucket after bucket did he send down, but not one brought up the refreshing draught he needed. Nothing--nothing could he think of that could conduce to his end. Once he plucked up courage and said imploringly as he went close up to the Emperor: "Go down earlier to-night my lord; you really do not allow yourself enough rest and will injure your health." Hadrian let him speak, and answered kindly: "I sleep in the morning. If you are tired, go to bed now." But Antinous remained, gazing, like his master, at the stars. He knew very few of the brilliant bodies by their names, but some of them were very dear to him, particularly the Pleiades which his father had pointed out to him and which reminded him of his home. There he had been so quiet and happy, and how wildly his anxious heart was throbbing now! "Go to bed, the second hour is beginning," said Hadrian. "Already!" said the boy; and as he reflected how soon that must be done which Verus had required of him, and then looked up again at the heavens, it seemed to him as though all the stars in the blue vault over his head had glided from their places and were dancing in wild and whirling confusion between the sky and the sea. He closed his eyes in his bewilderment; then, bidding his master good-night he lighted a torch and by its flaring and doubtful light descended from the tower. Pontius had erected this slight structure expressly for Hadrian's nightly observations. It was built of timber and Nile-mud and stood up as a tall turret on the secure foundation of an ancient watch-tower built of hewn stone, which, standing among the low buildings that served as storehouses for the palace, commanded a free outlook over all the quarters of the sky. Hadrian, who liked to be alone and undisturbed when observing the heavens, had preferred this erection--even after he had made himself known to the Alexandrians--to the great observatory of the Serapeum, from which a still broader horizon was visible.