‘What about this night?’ he asked himself with painful anxiety. He had left a guard upon the house and its treasures, but what guard had he set upon that old man’s life? The doors of the sick room might be locked ever so securely, and yet the assassin might enter. Wincher and his accomplice might know of that secret staircase, in spite of the old servant’s affectation of entire ignorance; and between the secret staircase and the sick chamber there was only a sliding panel. ‘I’ll go back to-night,’ said Lucius. ‘I should be a dastard if, with my present knowledge, I left that old man unprotected. I’ll go back, and get into the garden from the creek. I shall find the detective on his beat at the back, no doubt. I’ll warn him about the secret staircase; so that no one shall get to Mr. Sivewright’s room that way, at any rate.’ He lost no time in putting his resolve into execution. It was a few minutes past eleven, and the distance to Cedar House was about half an hour’s walk. Before midnight he would be there. Fortune favoured him. The night was dark, and there was no one to observe his trespass as he walked along the deserted wharf and stepped lightly across the untenanted barges. From one of these it was easy to get upon the low wall of Mr. Sivewright’s garden. He saw a light in the brewhouse, where he had found the entrance to the secret stair. The door was open, and the detective was lounging against the door-post, smoking his pipe and enjoying the night air. ‘Who’s there?’ he demanded in cautious tones, as Lucius’s light footstep sounded on the weedy gravel. ‘A friend—Davoren,’ answered Lucius, and then told the man the reason of his return. ‘This is a worse case than even I thought it,’ he said. ‘There has been an attempt to poison the old gentleman up-stairs, as well as to rob him.’ The man looked incredulous. Lucius briefly stated his grounds for this statement. ‘There has been nothing stirring here?’ he asked. ‘Nothing, except the beadles. They’re on short rations, and it seems to make ’em active. I’ve been in and out ever since you left.’ ‘Has Wincher gone to bed?’ ‘Two hours ago.’ ‘And you are sure he has never stirred since?’ ‘Quite sure. I’ve been past his door about every ten minutes or so, and have heard him and his wife snoring as peaceable as a pair of turtle-doves.’ ‘Well, I’ve come to share your watch till morning, if you’ve no objection. After the discovery I’ve just told you about, I couldn’t rest.’ ‘No objections, sir. If you’d brought a casebottle with a trifle of spirit it might have been welcome.’ ‘I am sorry that I omitted to provide myself with such a thing,’ answered Lucius politely. He showed the detective the door opening upon the secret staircase, and told him not to leave the brewhouse while he, Lucius, went up-stairs to see that all was right on the upper floor.