“We must take our chance about that,” Dunster remarked.  “If the mail boat doesn’t run, I presume there will be something else we can charter.”

The station-master looked the curiosity which he did not actually express in words.

“Money will buy most things, nowadays, sir,” he observed, “but if it isn’t fit for our mail boat, it certainly isn’t fit for anything else that can come into Harwich Harbour.  However, you’ll hear what they say when you get there.”

Mr. Dunster nodded and relapsed into a taciturnity which was obviously one of his peculiarities.  The young man strolled down the platform, and catching up with the inspector, touched him on the shoulder.

“Do you know who the fellow is?” he asked curiously.  “It’s awfully decent of him to let me go with him, but he didn’t seem very keen about it.”

The inspector shook his head.

“No idea, sir,” he replied.  “He drove up just two minutes after the train had gone, came straight into the office and ordered a special.  Paid for it, too, in Bank of England notes before he went out.  I fancy he’s an American, and he gave his name as John P. Dunster.”

The young man paused to light a cigarette.

“If he’s an American, I suppose that accounts for it,” he observed.  “He must be in a precious hurry to get somewhere, though.”

“A night like this, too!” the inspector remarked, with a shiver.  “I wouldn’t leave London myself unless I had to.  They say there’s a tremendous storm blowing on the east coast.  Here comes the train, sir—­just one saloon and the guard’s van.”

The little train backed slowly along the platform side.  The engine was splashed with mud and soaking wet.  The faces of the engine-driver and his companion shone from the dripping rain.  The station-master held open the door of the saloon.

“You’ve a rough journey before you, sir,” he said.  “You’ll catch the boat all right, though—­if it goes.  The mail train was very heavy to-night.  You should catch her up this side of Colchester.”

Mr. Dunster nodded.

“I am taking this young gentleman with me,” he announced shortly.  “It seems that he, too, missed the train.  I am much obliged to you, station-master, for your attention.  Good night!”

They were about to start when Mr. Dunster once more let down the window.

“By the way,” he said, “as it is such a wild night, you will oblige me very much if you will tell the engine-driver that there will be a five pound note for himself and his companion if we catch the mail.  Inspector!”

The inspector touched his hat.  The station-master had turned discreetly away.  He had been an inspector himself once, and sovereigns had been useful to him, too.  Then the train glided from the platform side, plunged with a scream through a succession of black tunnels, and with rapidly increasing speed faced the storm.