"That's just what I was going to do. You know I found that G was T, S was H, and V was E; well, I tried and tried, and I couldn't get any further. I wrote down the alphabet, and put V opposite E, and T opposite G, and S opposite H. I stared at it and stared at it, and all of a sudden—I don't know how I came to think of it—I noticed that E is the fifth letter from the beginning of the alphabet, and V is the fifth letter from the end. The same thing held good with the next letter: G was seventh from the beginning, and T was seventh from the end."
Diggory paused as though to see what effect this announcement would have on the faces of his friends.
"Well!" they exclaimed; "go on!"
"Why, then, I saw in a moment what they'd done: they'd simply transposed the whole alphabet—A. was Z, and Z was A!"
"Oh!" cried Jack Vance; "I see it now."
"Of course, it was as plain as print. I put the two alphabets side by side, one the right way and the other upside down, and I read the cipher in two minutes, and here's what you might call the translation."
As he spoke he held out a scrap of scribbling-paper. Jack Vance took it, and read as follows:—
"Meet in the 'gym' when the fellows pass on to supper. The two cans of water are standing inside the cupboard under the stairs."
Mugford stared at Jack Vance, and Jack stared at Diggory. "D'you see?" cried the latter eagerly.
"Yes."