The banker, it seemed, was about his business again, in one of those simple addition sums, which he sometimes solved correctly.
"To you," he said, after a moment's pause, with a glance in Loo's direction, "to you, it must appear that I am interfering in what is not my own business.

You are wrong there." He had clasped his hands across his abnormal waistcoat, and he half closed his eyes as he blinked at the fire.
"I am a sort of intermediary angel," he went on, "between private persons in France and their friends in England.

Nothing to do with state affairs, you understand; at least, very little.

Many persons in England have relations or property in France.

French persons fall in love with people on this side of the Channel, and vice versa.