He kept his news to himself, for he didn't want the police to interfere, but he had his own lot get into touch with Gresson and shadow him closely.

The man was very discreet but very mysterious, and he would disappear for a week at a time, leaving no trace.

For some unknown reason--he couldn't explain why--Blenkiron had arrived at the conclusion that Gresson was in touch with Ivery, so he made experiments to prove it.
'I wanted various cross-bearings to make certain, and I got them the night before last.

My visit to Biggleswick was good business.' 'I don't know what they meant,' I said, 'but I know where they came in.
One was in your speech when you spoke of the Austrian socialists, and Ivery took you up about them.

The other was after supper when he quoted the _Wieser Zeitung_.' 'You're no fool, Dick,' he said, with his slow smile.