He was not in the least sleepy; but after a while the vigil began to tell upon his nerves. He found it almost impossible to sit still and wait, perhaps in vain. He made innumerable trips across the room to the windows to look out into the bleak night. The landscape was blotted out. Not a light showed from the House on the Dunes; only the two lamps on the schooner at anchor in the Cove gleamed across the night. Eleven o'clock, twelve o'clock struck solemnly from the old clock on the stairs.
Once as he was looking out of the window, it seemed to him that the green light on the _Southern Cross_ was moving. But it was impossible that she should weigh anchor in the teeth of the rising storm. He was mistaken. Nay, he was sure. But it was rising, slowly, steadily, as though drawn by an invisible hand, to about the height of the masthead. There at last it stopped, and swung to the wind, to and fro, to and fro; high above its red companion, high above the deck.
And then, suddenly, as if to answer this mysterious manoeuvre, the green light, that earlier in the evening had glowed from a north window of the House on the Dunes, now flashed from an east window of the old farmhouse; flashed, then gleamed steadily. The light on the _Southern Cross_ was lowered slowly, then raised again. The light in the House on the Dunes vanished; soon flashed again and then vanished once more. Slowly the light in the schooner descended to its normal position. A moment later the green light appeared on the north side of the House on the Dunes, where it had been earlier, and shone there steadily.
Was it a signal to the Marquis de Boisdhyver? Tom tiptoed to the partition between his room and the South Chamber, and put his ear to the wall to listen. Not a sound reached him. He turned to the door to go into the corridor, and stood suddenly motionless. For there, advancing ever so cautiously down the hall, carrying a lighted candle in his hand, was the old Marquis. He was clad in night dress and cap, with a gayly-coloured dressing-gown worn over the white shirt. Slowly, silently, pausing every instant to listen; he stole on, gun in hand, and Tom followed him as cautiously and as quietly. Instead of turning to the right at the partition that divides the north and south wings of the Inn and going down stairs, the Marquis turned to the left, into the short hall that led directly to the great chamber occupied by Tom and Dan.