"You cannot reproach yourself in any way, sir!"
"Can I not?" said Dr. Cairn hoarsely. "Ah, Rob, you don't know!"
There came a rap on the door, and a local practitioner entered.
"This is a singular case, Dr. Cairn," he began diffidently. "An autopsy--"
"Nonsense!" cried Dr. Cairn. "Sir Elwin Groves had foreseen it--so had I!"
"But there are distinct marks of pressure on either side of the windpipe--"
"Certainly. These marks are not uncommon in such cases. Sir Michael had resided in the East and had contracted a form of plague. Virtually he died from it. The thing is highly contagious, and it is almost impossible to rid the system of it. A girl died in one of the hospitals this week, having identical marks on the throat." He turned to his son. "You saw her, Rob?"
Robert Cairn nodded, and finally the local man withdrew, highly mystified, but unable to contradict so celebrated a physician as Dr. Bruce Cairn.
The latter seated himself in an armchair, and rested his chin in the palm of his left hand. Robert Cairn paced restlessly about the library. Both were waiting, expectantly. At half-past two Felton brought in a tray of refreshments, but neither of the men attempted to avail themselves of the hospitality.
"Good," muttered Dr. Cairn. "Blessed is youth."
Silence fell again, upon the man's departure, to be broken but rarely, despite the tumultuous thoughts of those two minds, until, at about a quarter to three, the faint sound of a throbbing motor brought Dr. Cairn sharply to his feet. He looked towards the window. Dawn was breaking. The car came roaring along the avenue and stopped outside the house.
Dr. Cairn and his son glanced at one another. A brief tumult and hurried exchange of words sounded in the hall; footsteps were heard ascending the stairs, then came silence. The two stood side by side in front of the empty hearth, a haggard pair, fitly set in that desolate room, with the yellowing rays of the lamps shrinking before the first spears of dawn.
Then, without warning, the door opened slowly and deliberately, and Antony Ferrara came in.
His face was expressionless, ivory; his red lips were firm, and he drooped his head. But the long black eyes glinted and gleamed as if they reflected the glow from a furnace. He wore a motor coat lined with leopard skin and he was pulling off his heavy gloves.