"Who's this brother?"

"I know scarcely anything about him. His name's Rivière--he's a
half-brother. He turns up unexpectedly from the wilds of Canada, and
lives like a hermit, so Clifford tells me, in some tumbledown villa
outside Paris."

"What's he like?"

"I've never seen him."

"What's the scientific experiment?"

"Clifford told me something about it, but I forgot. I wasn't interested
in the slightest. No money in it, I could see at once. I told Clifford
so."

Sir Francis tugged at his watch impatiently. "He'll miss this train for
certain!"

"No; there he is!"

Matheson was striding rapidly through the press of people on the
platform. He quickly caught sight of his wife and father-in-law, and
came up with a gesture of apology.

"Sorry I'm so late. Very sorry, too, I shan't be able to travel with you
to-night."

"Experiment to finish?" queried Olive, with an unconcealed note of