I think it was Archie’s calm acceptance of my position as natural and becoming that restored my good temper. He was far too well bred to ask what crime I had committed, and I didn’t propose to enlighten him much. But as we swung up the moorland road I let him know that I was serving the Government, but that it was necessary that I should appear to be unauthenticated and that therefore I must dodge the police. He whistled his appreciation.

“Gad, that’s a deep game. Sort of camouflage? Speaking from my experience it is easy to overdo that kind of stunt. When I was at Misieux the French started out to camouflage the caravans where they keep their pigeons, and they did it so damned well that the poor little birds couldn’t hit ’em off, and spent the night out.”

We entered the white gates of a big aerodrome, skirted a forest of tents and huts, and drew up at a shanty on the far confines of the place. The hour was half past four, and the world was still asleep. Archie nodded towards one of the hangars, from the mouth of which projected the propeller end of an aeroplane.

“I’m by way of flyin’ that bus down to Farnton tomorrow,” he remarked. “It’s the new Shark-Gladas. Got a mouth like a tree.”

An idea flashed into my mind.

“You’re going this morning,” I said.

“How did you know?” he exclaimed. “I’m due to go today, but the grouse up in Caithness wanted shootin’ so badly that I decided to wangle another day’s leave. They can’t expect a man to start for the south of England when he’s just off a frowsy journey.”

“All the same you’re going to be a stout fellow and start in two hours’ time. And you’re going to take me with you.”

He stared blankly, and then burst into a roar of laughter. “You’re the man to go tiger-shootin’ with. But what price my commandant? He’s not a bad chap, but a trifle shaggy about the fetlocks. He won’t appreciate the joke.”

“He needn’t know. He mustn’t know. This is an affair between you and me till it’s finished. I promise you I’ll make it all square with the Flying Corps. Get me down to Farnton before evening, and you’ll have done a good piece of work for the country.”