"I see. Had the second marriage proved fruitful, the child of Mirza would have been—what shall we say?—smothered?"
"Damn it! What do you mean?"
"He was the rightful heir."
"Dr. Cairn," said Lashmore slowly, "you are probing an open wound. The fourth Baron Lashmore represents what the world calls 'The Curse of the House of Dhoon.' At Dhoon Castle there is a secret chamber, which has engaged the pens of many so-called occultists, but which no man, save every heir, has entered for generations. It's very location is a secret. Measurements do not avail to find it. You would appear to know much of my family's black secret; perhaps you know where that room lies at Dhoon?"
"Certainly, I do," replied Dr. Cairn calmly; "it is under the moat, some thirty yards west of the former drawbridge."
Lord Lashmore changed colour. When he spoke again his voice had lost its timbre.
"Perhaps you know—what it contains."
"I do. It contains Paul, fourth Baron Lashmore, son of Mirza, the Polish Jewess!"
Lord Lashmore reseated himself in the big armchair, staring at the speaker, aghast.
"I thought no other in the world knew that!" he said, hollowly. "Your studies have been extensive indeed. For three years—three whole years from the night of my twenty-first birthday—the horror hung over me, Dr. Cairn. It ultimately brought my grandfather to the madhouse, but my father was of sterner stuff, and so, it seems, was I. After those three years of horror I threw off the memories of Paul Dhoon, the third baron—"