“I can but bring on the old pains,” said the Spook.

“What do you mean, please?”

(This is where our study of the Commandant’s disease, biliary colic, first came in useful.)

“Vomiting,” the Spook answered. “Vomiting! Shivers! Such agony that he will roll about and scream for mercy! He knows well, but I shall choose my own time. Unless orders are obeyed today I forbid my mediums to grant further sittings under penalty of madness to themselves. Good-bye.”

“How can I make the Commandant do it?” Moïse asked.

Before a reply was possible both mediums had their fingers again thrown from the glass and appeared to experience a sensation which the sitter in his notes describes briefly as “electric shock.” The Control was obviously angry. Hill and I refused to venture any further, and we asked Moïse to say so to the Commandant. Moïse suggested that we should put our views in writing. We therefore wrote the Commandant a joint letter, in which we expressed our regret that he was unwell, and hoped he would be sufficiently recovered by the afternoon to begin the experiment. We ended by saying that in view of the Control’s threats we could not (for our own sakes as well as for the sake of the Commandant) go any further in the matter unless it was put in hand that day.

The Pimple hurried off with the letter and the record of the séance.

“There goes our last chance, old chap,” I said to Hill as soon as we were left alone. “If that doesn’t fetch him, we’ve failed.”

“Oh no,” said Hill, “we can always smash up a sentry a bit. They’ll lock us up quick enough for that. We can tell the Commandant privately we were spooked into doing it!”

“Right-o!” I agreed. “We’ll try that next. I want to biff that little beast with the top boots, anyway.”