In reality, he was gazing into space, wondering about what had just been said.
"Then you think he died a natural death ?" he asked, suddenly turning on his companion.

"You don't think there's--anything wrong ?" The doctor shook his head calmly.
"I think he died of precisely what I should have expected him to die of," he answered.

"Heart failure.

It came upon him quite suddenly.

You see, he was in the act of taking off his boots.