But they were not. The next thing I took out was a key. It was a little one, and the queerest shape I ever saw. It was fastened to a steel chain; at one end of the chain was a padlock. Attached to the handle of the key was a kind of flying label; on it this was written:

“To Mary Blyth. This is the key of 84, Camford Street. The lock is high up on the left-hand side of the door. There is no keyhole. You will see a green spot. Press the key against the spot and it will enter the lock. Push home as far as it will go, then jerk upwards, and the door will open. Don’t try to enter when anyone is looking. Directly you get it, tear off this label and burn it. Then pass the chain about your waist, underneath your dress, and snap the padlock. If you lose the key, or let it go for a moment from your possession, may the gods burn up the marrow in your bones. And they will.”

“That’s cheerful reading,” I observed, when I had read the label to an end. I passed it to Mr. Paine.

“It is curious,” he admitted. “In which respect it’s of a piece with all the rest.”

When Emily read it her eyes and mouth opened as wide as they very well could do.

“I never!” she cried. “Isn’t it mysterious?”

“What shall I do?” I asked, when the chain and key had been returned to me.

Mr. Paine considered.

“You had better do as instructed—burn the label; that is, after we have taken a copy. There is nothing said against your doing that; and, if you have a copy, it will prevent your memory playing you false. As for the key itself—will it do you any harm to fasten it to your waist in the manner directed?”

“Except that it’s a bit too mysterious for my taste. Some folks like mysteries; I don’t.”