The cause of death, in Macalister’s case, was heart failure, an unsuspected weakness of that organ being brought to light at the inquest; but, according to the medical testimony, deceased must have undergone unnaturally violent exertions to bring about death. In other respects, the circumstances of the two cases were almost identical. The door of the Greek Room was locked upon the inside and the keys were found on the floor. From the detector watches in the other rooms it was evident that his death must have taken place about three o’clock. Nothing was missing, and the jewels in the harp had not been tampered with. But, most amazing circumstance of all, imprinted upon the dry plaster of Paris which, in accordance with the instructions of the mysteriously absent Moris Klaw, had nightly been placed around the case containing the harp, _were the marks of little bare feet!_ A message sent, through the willing agency of Inspector Grimsby, to the Wapping abode of the old curio dealer, resulted in the discovery that Moris Klaw was abroad. His daughter, however, reported having received a letter from her father which contained the words-- “Let Mr. Coram keep the key of the case containing the Athenean Harp under his pillow at night.” “What does she mean?” asked Coram. “That I am to detach that particular key from the bunch or place them all beneath my pillow?” Grimsby shrugged his shoulders. “I’m simply telling you what she told me, sir.” “I should suspect the man to be an impostor,” said Coram, “if it were not for the extraordinary confirmation of his theory furnished by the footprints. They certainly looked like those of a woman!” Remembering how Moris Klaw had acted, I sought out the constable who had been on duty at the corner of South Grafton Square on the night of the second tragedy. From him I elicited a fact which, though insignificant in itself, was, when associated with another circumstance, certainly singular. A Pickford traction engine, drawing two heavy wagons, had been driven round the Square at 3 A.M., the driver thinking that he could get out on the other side. That was practically all I learned from the constable, but it served to set me thinking. Was it merely a coincidence that, at almost the exact hour of the previous tragedy, a heavy pantechnicon had passed the Museum? “It’s not once in six months,” the man assured me, “that any vehicle but a tradesman’s cart goes round the Square. You see, it doesn’t lead anywhere, but this Pickford chap he was rattling by before I could stop him, and though I shouted he couldn’t hear me, the engine making such a noise, so I just let him drive round and find out for himself.” I now come to the event which concluded this extraordinary case, and, that it may be clearly understood, I must explain the positions which we took up during the nights of the following week; for Coram had asked me to take a night watch, with himself, Grimsby, and Beale, in the Museum.