SOLVING CIPHER SECRETS

IT might be well to take this opportunity to remind readers—and particularly those who are unacquainted with our cipher department—that the publishers of FLYNN'S WEEKLY DETECTIVE FICTION are prepared to supply back numbers of the magazine that contain "Solving Cipher Secrets" at a price of ten cents a copy with the exception of copies over a year old, which automatically become twenty cents.

Now, go on with the story:

Continuing the analysis of transposition cipher No. 73 from previous articles, we have so far determined that a seven-letter key was employed, and that the message was therefore transcribed in lines of seven letters, forming two columns of eleven letters each, and five columns of ten letters each.

The order of these columns in the cryptogram is, of course, dependent upon the numerical key. But this key is as yet undetermined. Consequently the exact composition of the several columns is still unknown.

By assuming, however, that the long columns come first in the cryptogram, and then that they come last, it will be possible to find the maximum variation that can occur in their make-up, and to learn just which letters can be definitely assigned to their proper columns, and which cannot.

For example, if the two eleven-letter columns are assumed to come first in cipher No. 73, the seven columns would stand as shown herewith. Observe that the cryptogram has been transcribed into this formation by columns downward, and from left to right.

On the other hand, if the five ten-letter columns are assumed to come first, the final letter, E, of column 1, would belong at the top of column 2. And the last two letters, IE, of column 2, would have to be carried to the top of column 3.

Similarly, the last two letters in columns 3, 4, and 5, would be transferred, respectively, to the tops of columns 4, 5, and 6. Since columns 6 and 7 are now supposed to contain eleven letters each, however, only the one letter, D, would have to be carried from column 6 to column 7.

In determining the order of these columns, it is convenient to use a set of specially prepared paper slips, each of which bears, evenly spaced, the letters of one of the supposed columns. Seven such slips for the present cryptogram are shown herewith. Note that letters whose columns are known are given in capitals, and that those of doubtful location are in small type.

On slip 2, for example, HNIAEUDSR may be definitely taken as of the column headed by that key number in the original set-up. The lone "e," however, may have occurred at the foot of column 1. Similarily, the "ie" may have been located at the head of column 3; or these letters may have been divided, "i" going to column 2, and "e" to column 3. And so on.

However, having prepared the special slips, it remains now to use them in developing the translation of the cryptogram, and in determining the numerical key by which the transposition was effected. Instructions for accomplishing these things will be given next week.

Cipher No. 79 (W. A. Cooke), of three weeks ago, conveyed the message; "The brain, like every other part of the body, needs exercise. Try ciphers!"

This is a multiple alphabet system using an enciphered key and indicator, and operable on a Vigenère cipher square, or other apparatus using straight A-to-Z alphabets. In deciphering, every time the indicator, Z, is encountered, the key changes, and the following enciphered letter, though still in the preceding key, indicates the next alphabet, as illustrated herewith:

Key:      H       P           K ...
Cipher:   H A O G W T Q G P O Z ...
Message:    T H(z)   E B R A(z) ...

The first letter of the cryptogram was the initial key letter. A weak point in this system is that sequences of letters in the same key would come out in the same line when tried by the familiar process of "running down the alphabet."

Next on tap is the solution to last week's "Q. and A." cryptogram. No. 83:

Question: What are the commonest of the vitriols?

Answer: Blue vitriol, or copper sulphate; green vitriol, or iron sulphate; and white vitriol, or zinc sulphate.

To decipher No. 84 (H. E. Burnett), merely take the second and next to last letters of each group, using dashes for word spaces, and get the message: "Not all who. try succeed."

As to the new ciphers, in No. 86 you are confronted with a simple substitution cipher of more than average difficulty. But try some of the common suffixes, and don't let the long words scare you. With probably one exception they are all ordinary ones.

The vowel test will tell you whether No. 87 is a transposition or substitution cipher, and the length, thirty-six letters, should be significant. Can you do the rest?

Finally, if you know the ropes, no hints whatever should be necessary with No. 88, Do your level best, and let us know what luck you have. We're here to help you. Answer to No. 88 will be published in three weeks. Nos. 86 and 87, also No. 82—of October 15—will be fully explained next week.

CIPHER No. 86 (Lewis Trent, New York, N. Y.).

AVMJPB,  POLING  LOPQ-CDLAU,
NHODK  LONIHE  KEUHNQ.  KHXUOS
SOLVD-XJRUO,  YVDHK  BHVOCVKQ
KELDN,  SHERLOCK  ZHKNVPU,  KJEA-
VDW  YGOVLM  XJEVPU  UDVWYLK.

CIPHER No. 87 (J. Lloyd Hood, Bastrop, Texas).

OAT  R  THE  HER  NE  READ  NIYD  MY
BOGG  HUE  FRSA  UIE

CIPHER No. 88 (Edward H. Thimme, Albany, New York).

THCSF  JGRTU  KGNLU  TLPHZ
KMOKO  WJFXR  QHTMH  HUKCO
GEBEK  OHVEU  CXHT

Readers are requested to include translations and explanations with ciphers submitted to this department for publication. This is necessary to insure the answers being published in subsequent issues.