Graham's Magazine, Vol. XIX, No. 1, July 1841 - Various

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and, so placed, a might stand for n and n for a, o for b and b for o, &c. &c. This, again, having an air of regularity which might be fathomed, the key alphabet might be constructed absolutely at random.

Thus,	a might stand for p
	b might stand for x
	c might stand for u
	d might stand for o,	&c.

The correspondents, unless convinced of their error by the solution of their cipher, would no doubt be willing to rest in this latter arrangement, as affording full security. But if not, they would be likely to hit upon the plan of arbitrary marks used in place of the usual characters. For example,

(	might be employed for	a
.	might be employed for	b
:	might be employed for	c
;	might be employed for	d
)	might be employed for	e,	&c.

A letter composed of such characters would have an intricate appearance unquestionably. If, still, however, it did not give full satisfaction, the idea of a perpetually shifting alphabet might be conceived, and thus effected. Let two circular pieces of pasteboard be prepared, one about half an inch in diameter less than the other. Let the centre of the smaller be placed upon the centre of the larger, and secured for a moment from slipping; while radii are drawn from the common centre to the circumference of the smaller circle, and thus extended to the circumference of the greater. Let there be twenty-six of these radii, forming on each pasteboard twenty-six spaces. In each of these spaces on the under circle write one of the letters of the alphabet, so that the whole alphabet be written—if at random so much the better. Do the same with the upper circle. Now run a pin through the common centre, and let the upper circle revolve, while the under one is held fast. Now stop the revolution of the upper circle, and, while both lie still, write the epistle required; using for a that letter in the smaller circle which tallies with a in the larger, for b that letter in the smaller circle which tallies with b in the larger, &c. &c. In order that an epistle thus written may be read by the person for whom it is intended, it is only necessary that he should have in his possession circles constructed as those just described, and that he should know any two of the characters (one in the under and one in the upper circle) which were in juxta-position when his correspondent wrote the cipher. Upon this latter point he is informed by looking at the two initial letters of the document, which serve as a key. Thus, if he sees a m at the beginning, he concludes that, by turning his circles so as to put these characters in conjunction, he will arrive at the alphabet employed.

At a cursory glance, these various modes of constructing a cipher seem to have about them an air of inscrutable secresy. It appears almost an impossibility to unriddle what has been put together by so complex a method. And to some persons the difficulty might be great; but to others—to those skilled in deciphering—such enigmas are very simple indeed. The reader should bear in mind that the basis of the whole art of solution, as far as regards these matters, is found in the general principles of the formation of language itself, and thus is altogether independent of the particular laws which govern any cipher, or the construction of its key. The difficulty of reading a cryptographical puzzle is by no means always in accordance with the labor or ingenuity with which it has been constructed. The sole use of the key, indeed, is for those au fait to the cipher; in its perusal by a third party, no reference is had to it at all. The lock of the secret is picked. In the different methods of cryptography specified above, it will be observed that there is a gradually increasing complexity. But this complexity is only in shadow. It has no substance whatever. It appertains merely to the formation, and has no bearing upon the solution, of the cipher. The last mode mentioned is not in the least degree more difficult to be deciphered than the first—whatever may be the difficulty of either.

In the discussion of an analogous subject, in one of the weekly papers of this city, about eighteen months ago, the writer of this article had occasion to speak of the application of a rigorous method in all forms of thought—of its advantages—of the extension of its use even to what is considered the operation of pure fancy—and thus, subsequently, of the solution of cipher. He even ventured to assert that no cipher, of the character above specified, could be sent to the address of the paper, which he would not be able to resolve. This challenge excited, most unexpectedly, a very lively interest among the numerous readers of the journal. Letters were poured in upon the editor from all parts of the country; and many of the writers of these epistles were so convinced of the impenetrability of their mysteries, as to be at great pains to draw him into wagers on the subject. At the same time, they were not always scrupulous about sticking to the point. The cryptographs were, in numerous instances, altogether beyond the limits defined in the beginning. Foreign languages were employed. Words and sentences were run together without interval. Several alphabets were used in the same cipher. One gentleman, but moderately endowed with conscientiousness, inditing us a puzzle composed of pot-hooks and hangers to which the wildest typography of the office could afford nothing similar, went even so far as to jumble together no less than seven distinct alphabets, without intervals between the letters, or between the lines. Many of the cryptographs were dated in Philadelphia, and several of those which urged the subject of a bet were written by gentlemen of this city. Out of, perhaps, one hundred ciphers altogether received, there was only one which we did not immediately succeed in resolving. This one we demonstrated to be an imposition—that is to say, we fully proved it a jargon of random characters, having no meaning whatever. In respect to the epistle of the seven alphabets, we had the pleasure of completely nonplus-ing its inditer by a prompt and satisfactory translation.

The weekly paper mentioned, was, for a period of some months, greatly occupied with the hieroglyphic and cabalistic-looking solutions of the cryptographs sent us from all quarters. Yet with the exception of the writers of the ciphers, we do not believe that any individuals could have been found, among the readers of the journal, who regarded the matter in any other light than in that of a desperate humbug. We mean to say that no one really believed in the authenticity of the answers. One party averred that the mysterious figures were only inserted to give a queer air to the paper, for the purpose of attracting attention. Another thought it more probable that we not only solved the ciphers, but put them together ourselves for solution. This having been the state of affairs at the period when it was thought expedient to decline farther dealings in necromancy, the writer of this article avails himself of the present opportunity to maintain the truth of the journal in question—to repel the charges of rigmarole by which it was assailed—and to declare, in his own name, that the ciphers were all written in good faith, and solved in the same spirit.

A very common, and somewhat too obvious mode of secret correspondence, is the following. A card is interspersed, at irregular intervals, with oblong spaces, about the length of ordinary words of three syllables in a bourgeois type. Another card is made exactly coinciding. One is in possession of each party. When a letter is to be written, the key-card is placed upon the paper, and words conveying the true meaning inscribed in the spaces. The card is then removed and the blanks filled up, so as to make out a signification different from the real one. When the person addressed receives the cipher, he has merely to apply to it his own card, when the superfluous words are concealed, and the significant ones alone appear. The chief objection to this cryptograph is the difficulty of so filling the blanks as not to give a forced appearance to the sentences. Differences, also, in the handwriting, between the words written in the spaces, and those inscribed upon removal of the card, will always be detected by a close observer.