'Give you a dead-latch key! a pretty notion!'

'I wouldn't give it to any man—not to all the detective squad in New York.'

'Look here, my friend, I am M——, pretty well known in this town. I have a good many opportunities in the course of my business to do people good turns, and not a few to do them ill turns. It is a convenient vocation to pay off scores, particularly to persons of your sort. If you will give me that key, I'll make it worth your while the first chance I have. If you don't, you'll be sorry; that's all."

I gave him a significant look as I concluded. He looked me in the face a minute—as if to see how much I meant, or if I suspected anything; then turned and ran up stairs. In a few moments he came down, and handed me the key. I took it with satisfaction.

'Now,' said I, 'you'll have no objections to telling me where your sister-in-law's room in the house is.'

'Third story, back room, second door to the left from the head of the stairs.'

'Thank you, good night.'

We walked rapidly to —— street, and reaching the house, I stopped a moment to examine my pistols, by the street lamp, and then softly opened the door. Clarke and I stepped in, and I shut the door.

Leaving my comrade in the hall, I crept noiselessly up stairs, and tapped at the door of the room.

'Who is there?' called out a woman's voice. 'Open the door,' I replied, 'and I'll tell you what I want.'