to my ear and earnestly continued: "Now listen, and be guided by my instructions. You will not be able to enter by the front door, as it is guarded, and you cannot pass without removing your mask. But the window on the left-hand balcony is at your service. It is open, and the man appointed to keep intruders away, has been bribed to let you pass. Once inside the house, join the company sans céremonie; and do not hesitate to converse with any one who addresses you by the countersign. Promptly at ten o'clock look around you for a domino in plain black. When you see him move, follow him, but with discretion, so that you may not seem to others to be following. Sooner or later he will pause and point to a closed door. Notice that door, and when your guide has disappeared, approach and enter it without fear or hesitation. You will find yourself in a small apartment connecting with the library.
"There is but one thing more to say. If the wineglass you will observe on the library table smells of wine, you may know your father has had his nightly potion and gone to bed. But if it contains nothing more than a small white
