certain it must be a cryptogram or code-writing of some sort; and if that's the case, I think I might back myself to read it—with a little time." For I well remembered the case of the "Flitterbat Lancers," and the lesson in cypher-reading which Hewitt then gave me.
"Come," my friend replied, much interested, "let's see how you do it. Meantime we'll get on with our lunch."
I took a pencil and a spare sheet of paper, and I studied those figures all through lunch and for some little time after. It soon became plain that the problem was much more difficult than it looked, and I said so. "At the first glance," I said, "it looked a fairly easy cypher; but as a matter of fact, I don't think it's easy at all. One assumes, of course, that the figures stand for letters, and on that assumption two or three peculiarities are noticeable. First, the highest number written here is 23, so that all the letters indicated, in whatever order they may come, are within the compass of the twenty-six letters of the alphabet. Next, the numbers most frequently repeated, if we except the noughts, are 5 and 20, which occur seven times each. Now, the vowel most frequently occurring in average English writing is e, and you will at once perceive that e is number five in the alphabet, counting from the
