"I tell you what," said Mike, "How about tying a string at the top of the steps?"

"Yes, Napoleon would have done that, too. Hats off to Comrade Jackson, the man with the big brain!"

The floor of the dormitory was below the level of the door. There were three steps leading down to it. Psmith switched on his torch and they examined the ground. The leg of a wardrobe and the leg of Jellicoe's bed made it possible for the string to be fastened in a satisfactory manner across the lower step. Psmith surveyed the result with approval.

"Dashed neat!" he said. "Practically the sunken road which dished the Cuirassiers at Waterloo. I seem to see Comrade Spiller coming one of the finest purlers in the world's history."

"If they've got a torch—"

"They won't have. If they have, stand by and grab it at once; then they'll charge forward and all will be well. If they have no light, fire into the brown with a jug of water. Lest we forget, I'll collar Comrade Jellicoe's jug now and keep it handy. A couple of sheets would also not be amiss—we will enmesh the enemy!"

"Right ho!" said Mike.

"These humane preparations being concluded," said Psmith, "we will retire to our posts and wait. Comrade Jellicoe, don't forget to breathe like an asthmatic sheep when you hear the door opened; they may wait at the top of the steps, listening."

"You are a lad!" said Jellicoe.

Waiting in the dark for something to happen is always a trying experience, especially if, as on this occasion, silence is essential. Mike was tired after his journey, and he had begun to doze when he was jerked back to wakefulness by the stealthy turning of the door handle; the faintest rustle from Psmith's direction followed, and a slight giggle, succeeded by a series of deep breaths, showed that Jellicoe, too, had heard the noise.