HAT is a cryptogram?
Secret writing, of course, is a generally accepted meaning.
But is secret writing always cryptography?
Would a message written, say, in an established system of shorthand, or translated into a foreign language, unknown to any who might intercept or examine the communication, be properly called a cryptogram?
This interesting question is brought up by W. W. Rouse Ball in the eighth edition (London, 1919), of his "Mathematical Recreations," in which is included a chapter on cryptography, a subject not discussed in the previous editions.
Ball defines a cryptogram as a communication that may be freely given to all the world, and yet be intelligible only to those who have the key.
While foreign languages, or recognized language notations, cannot by this rule be classed as ciphers, such noncryptographic devices may, on occasion, be quite adequate for purposes of secret communication.
For example, during the St. Mihiel drive in the World War it was found that the Germans, intercepting the telegraphic dots and dashes, could easily read messages in any of the classical languages. But they were completely nonplused by the signals of two Choctaws communicating in their own language.
A similar scheme, according to Ball, was used by the British during the Sepoy Mutiny, when intercepted messages, written in English, but using the letters of the Greek alphabet, effectively resisted decipherment at the hands of the enemy.
An ingenious communication of a similar nature was resorted to by a lady who intended to puzzle Philip Thicknesse, author of "A Treatise on the Art of Decyphering, and of Writing in Cypher, with an Harmonic Alphabet," published at London in 1772.
In this instance the epistle was also in English, first rendered, as shown below, in the French orthography, but, as Thick - nesse received it, written in Etruscan characters, an ancient alphabet which our readers will find reproduced in Isaac Taylor's "The Alphabet," London, 1883.
"Sur, as yeux air il, doux comme & change the climat: here, yeux mai have game, fiche, duc, fat mutin, foule, porc, aile, port, fruit, & admirable menehette an butter; an mi sistre (a joli nymphe) tu chat tu yeux, & sing yeux an ode, tu the lute, or violin: yeux canne have a stéble for ure hors, & a place for ure chaise. Mi son met a physician neér the river, tissé fêtal signe! thé sal, the pour Docteur dos grive about the affaire, oing tu the rude Squire:—but pardon mi long lettre, pré doux comme tu us about mai, if yeux canne: mi service tu ure niece: hoüe dos Raffe doux? Adieu mi friend, * * * * * * * * P. S.—— Pré doux comme; for ure pour Nenni seize but feu beaux."
We have not learned that the Hon. Mr. Thicknesse accepted this invitation. But if he did, could we have cautioned him, it would have been to say that the writer of such a delightful missive could only have a most charming sister.
As a still earlier example of the same general class of communications may be cited the celebrated Diary of Samuel Pepys, once believed to be in cipher, but found, aside from a few modifications, actually to have been written in Tachy-graphy, a shorthand invented by J. Shelton, first published in 1620, of which Pepys.employed the sixth edition issued in 1641.
To some extent Pepys turned the Shelton shorthand into cipher by omitting vowels, by using arbitrary symbols of his own invention for certain words, terminations, and particles, and by the insertion of nulls or nonsignificants. The last mentioned device and the use of foreign languages was- resorted to when the subject matter, according to Ball, was such as could scarcely be expressed with decency.
A knowledge of Tachy-graphy, however, and the several languages used in the Pepys Diary would afford adequate means of deciphering that famous document. Likewise the Thicknesse note would occasion no difficulty for one familiar with the Etruscan alphabet.
The Sepoy Mutiny communication, similarly, would have been readily interpreted by any one knowing the English language and the Greek alphabet; as would also the World War messages, by a Choctaw.
As far as results go the employment of such artifices as these might often be as effective as the use of cipher. By Ball's test of exposure to the whole world, as has just been shown, however, they cannot be properly classified as cipher systems.
A cryptogram is thus a communication which, unless resolved by the special processes of cryptanalysis, is intelligible only to those in possession of the key.
Here are two cryptograms, submitted by our readers. Can you resolve them without their keys?
CIPHER No. 6 (Dr. G. A. Ferrell, Bessemer, Alabama).
HEEAS LCTDB LRINY LIIEL LSECE PSCET AHNHN IBEAG EOPUA ERTHT SIUEI ENRTA AWBII T
CIPHER No. 7 (Francis A. Gauntt, Chicago, Illinois).
60-46-45-58-20-86-48-20-79-36-29-45-36-47- 77-47-39-57-66-29-79-66-37-88-56-60-68-37- 38-39-66-26-75-83-29-45-38-20-68-59-26-46- 70-50-65-57-56-65-60-58-65-70-26-56-66.
The following simple substitution alphabet based on the key word KNAVERY was used in cipher No. 5, last week's crypt. Note how the cipher alphabet was taken cut by "alternate verticals" starting with the last column downward:
K N A V E R Y B C D F G H I J L M O P Q S T U W X Y Z A B C D E F G H I J K L M Y I S Q H R E G P Z X O F N O P Q R S T U V W X Y Z V A D M W U L C N K B J T
There are still two weeks in which to solve one or two of The National Puzzlers' League contest crypts published in last week's department. The first three prizes are copies of "Real Puzzles," a book dealing with the history, construction, and solution of several standard types of word-puzzles, with one hundred and fifty original examples. Have you mailed your entry?
The solutions to this week's ciphers Nos. 6 and 7, and to No. 1, Mr. Davidson's contest cipher of three weeks ago, will be published next week.
There will also be some chat, more ciphers, and other items of interest in next week's issue.