"I believe I can put that matter to the test," he declared. "In my dream, as I turned into the lane where the house was--the house of the mummy--there was a patch covered with deep mud, where at some time during the evening a quantity of water had been spilt. I stepped upon that patch, or dreamt that I did. We can settle the point." He sat down on the bed beside his son, and, stooping, pulled off one of his slippers. The night had been full enough of dreadful surprises; but here was yet another, which came to them as Dr. Cairn, with the inverted slipper in his hand, sat looking into his son's eyes. The sole of the slipper was caked with reddish brown mud. CHAPTER XVI LAIR OF THE SPIDERS "We must find that house, find the sarcophagus--for I no longer doubt that it exists--drag it out, and destroy it." "Should you know it again, sir?" "Beyond any possibility of doubt. It is the sarcophagus of a queen." "What queen?" "A queen whose tomb the late Sir Michael Ferrara and I sought for many months, but failed to find." "Is this queen well known in Egyptian history?" Dr. Cairn stared at him with an odd expression in his eyes. "Some histories ignore her existence entirely," he said; and, with an evident desire to change the subject, added, "I shall return to my room to dress now. Do you dress also. We cannot afford to sleep whilst the situation of that house remains unknown to us." Robert Cairn nodded, and his father stood up, and went out of the room. Dawn saw the two of them peering from the balcony upon the streets of Port Said, already dotted with moving figures, for the Egyptian is an early riser. "Have you any clue," asked the younger man, "to the direction in which this place lies?" "Absolutely none, for the reason that I do not know where my dreaming left off, and reality commenced. Did someone really come to my window, and lead me out through another room, downstairs, and into the street, or did I wander out of my own accord and merely imagine the existence of the guide? In either event, I must have been guided in some way to a back entrance; for had I attempted to leave by the front door of the hotel in that trance-like condition, I should certainly have been detained by the _bowwab_. Suppose we commence, then, by inquiring if there is such another entrance?" The hotel staff was already afoot, and their inquiries led to the discovery of an entrance communicating with the native servants' quarters. This could not be reached from the main hall, but there was a narrow staircase to the left of the lift-shaft by which it might be gained. The two stood looking out across the stone-paved courtyard upon which the door opened. "Beyond doubt," said Dr. Cairn, "I might have come down that staircase and out by this door without arousing a soul, either by passing through my own room, or through any other on that floor."