A pack of cards is sometimes made the vehicle of a cipher, in this manner. The parties determine, in the first place, upon certain arrangements of the pack. For example: it is agreed that, when a writing is to be commenced, a natural sequence of the spots shall be made; with spades at top, hearts next, diamonds next, and clubs last. This order being obtained, the writer proceeds to inscribe upon the top card the first letter of his epistle, upon the next the second, upon the next the third, and so on until the pack is exhausted, when, of course, he will have written fifty-two letters. He now shuffles the pack according to a preconcerted plan. For example: he takes three cards from the bottom and places them at top, then one from top, placing it at bottom, and so on, for a given number of times. This done, he again inscribes fifty-two characters as before, proceeding thus until his epistle is written. The pack being received by the correspondent, he has only to place the cards in the order agreed upon for commencement, to read, letter by letter, the first fifty-two characters as intended. He has then only to shuffle in the manner pre-arranged for the second perusal, to decipher the series of the next fifty-two letters—and so on to the end. The objection to this cryptograph lies in the nature of the missive. _A pack of cards_, sent from one party to another, would scarcely fail to excite suspicion; and it cannot be doubted that it is far better to secure ciphers from being considered as such, than to waste time in attempts at rendering them scrutiny-proof, when intercepted. Experience shows that the most cunningly constructed cryptograph, if suspected, can and will be unriddled. An unusually secure mode of secret intercommunication might be thus devised. Let the parties each furnish themselves with a copy of the same edition of a book—the rarer the edition the better—as also the rarer the book. In the cryptograph, numbers are used altogether, and these numbers refer to the locality of letters in the volume. For example—a cipher is received commencing, 121-6-8. The party addressed refers to page 121, and looks at the sixth letter from the left of the page in the eighth line from the top. Whatever letter he there finds is the initial letter of the epistle—and so on. This method is very secure; yet it is _possible_ to decipher any cryptograph written by its means—and it is greatly objectionable otherwise, on account of the time necessarily required for its solution, even with the key-volume.