Jezebel's Daughter

by Wilkie Collins

"It's simply incomprehensible."

"Not in the least. She knew the use to which Jack had put her antidote, and (in her ignorance of chemistry) she was eager to be prepared for any consequences which might follow. Can you guess on what chance I calculated, when I consented to interpret the cipher?"

"On the chance that it might tell you what poison she had given to Mrs. Wagner?"

"Well guessed, Mr. Glenney!"

"And you have actually discovered the meaning of these hieroglyphics?"

He laid a second sheet of paper on the table.

"There is but one cipher that defies interpretation," he said. "If you and your correspondent privately arrange to consult the same edition of the same book, and if your cipher, or his, refers to a given page and to certain lines on that page, no ingenuity can discover you, unaided by a previous discovery of the book. All other ciphers, so far as I know, are at the mercy of skill and patience. In this case I began (to save time and trouble) by trying the rule for interpreting the most simple, and most elementary, of all ciphers—that is to say, the use of the ordinary language of correspondence, concealed under arbitrary signs. The right way to read these signs can be described in two words. On examination of the cipher, you will find that some signs will be more often repeated than others. Count the separate signs, and ascertain, by simple addition, which especial sign occurs oftenest—which follows next in point of number—and so on. These comparisons established, ask yourself what vowel occurs oftenest, and what consonant occurs oftenest, in the language in which you suppose the cipher to be written. The result is merely a question of time and patience."

"And this is the result?" I said, pointing to the second sheet of paper.

"Read it," he answered; "and judge for yourself."

The opening sentence of the interpreted cipher appeared to be intended by Doctor Fontaine to serve the purpose of a memorandum; repeating privately the instructions already attached by labels to the poison called "Alexander's Wine," and to its antidote.