"Quarrelling, no! One doesn't quarrel with a dying man," he answered.

"A dying man!" I repeated.

He nodded.

"He was on the verge of a collapse just now," he said. "I honestly fear that he will not live many more hours. Yet, though I could fill in his death certificate plausibly enough, if you were to ask me honestly to-day what was the matter with him, I could not tell you. Do you mind if I wire for a friend of mine to come down and see him?"

"By all means," I answered; "you mean a specialist, I suppose?"

"Yes!"

"On the heart?" I asked.

"No! a toxicologist!" Rust remarked dryly.

I glanced into his face. He was in deadly earnest.

"You believe—"