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S O L V I N G C I P H E R S E C R E T S Edited by M. E . Ohaver

I N C L U D I N G T E N S T A N D A R D S F O R M E A S U R I N G T H E M E R I T O F A C I P H E R S Y S ­T E M , A L S O T W O B L A I R C I P H E R S , O T H E R A N S W E R S A N D A L I S T O F S O L V E R S

P* R S V R y P R F C T M N V R K P T H S P R C P T S T N

TH I S inscription, say the puzzle books, is to be found over the en­trance to an ancient and historic

monastery in England. A s the story goes, it was originally paint­

ed in two colors; the consonants being in black, and the vowels, of which only E is used, in red. A n d it is said that the red letters faded out, leaving the string of irreg­ular ly spaced consonants to perplex the curious.

T h e inscription is so well known that it is unnecessary to append its translation. B u t speaking of " precepts," our own list of the essentials of cipher composition, an­nounced in this issue of March 2 6 , has, through the unavoidable pressure of more urgent material, been temporarily side­tracked, but by no means overlooked or forgotten.

A n d after due consideration, it seems ad­visable to present the entire series at once, leaving the discussion of the individual statements for subsequent issues.

Here, then, are ten standards by which it may be well to measure the relative merit of a cipher system:

I — A cipher should employ symbols that are easy to write, read, and pronounce, and that are transmissible by existing modes of communication.

2 — I t should express a given message in the shortest practicable cryptogram.

3 — I ts security or use should not be de­pendent upon any limitations in the text of the message material.

4 — I t should permit easy and rapid en-cipherment and decipherment, and by one'or more persons.

5 — Any rules, tables, books, apparatus, ma­chines, or other equipment which it might employ, should not render it impracticable for its intended purpose.

6 — I t should be capable of a practically un­limited number of variations, securable by keys which are easy to remember, change, and communicate.

7— Without the keys, any number of cryp­tograms in the same or different keys should be absolutely undecipherable, even with full knowledge of the system and possession of the necessary apparatus.

8 — Any comparison of one or more cryp­tograms with all or part of their translations, or with their encipherments in other systems, should not lead to any further decipherment.

g,—With the key, method, and equipment, the cipher should be capable of only one i n ­terpretation.

1 0 — I f required, it should lend itself to use without suspicion.

T h e first of these propositions has a l ­ready been discussed in the March 12 issue; and others wi l l be considered in forthcom­ing installments, beginning next week.

I n the meantime we should be glad to hear from our reader on the subject. I t is believed that these propositions cover the ground. B u t some points of more or

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S O L V I N G C I P H E R S E C R E T S 479

less importance may have been overlooked; and suggestions, additions, or criticisms are invited.

L . H . P . , Chicago, has written us interest­ingly about his solutions of the B l a i r c i ­phers—see F L Y N N ' S W E E K L Y for J u l y 25

and August 15, 1925—inquiring also if a certain other cipher, propounded by B l a i r , has ever been explained.

T h e cipher in question was published by B l a i r with its translation in his cipher a r t i ­cle in Rees's Cyclopaidia, but without any suggestion as to the method involved. How­ever, B l a i r did not claim any particular ad­vantages for the system, offering it more on account of its somewhat remarkable ap­pearance of an unknown language.

Incidentally, this cipher fails to meet the requirements of propositions 2, 7, and 8, herewith. F o r the cryptogram is more than twice as long as the message it conveys; it is decipherable without the key; and it can be readily matched up with its translation.

Nevertheless, it should afford an interest­ing half hour's study. Certain errors in the original have been corrected here by using symbols found elsewhere in the cryptogram.

C I P H E R No. 23 (Wil l iam B l a i r ) . Cryptogram: S ika jygara a fuva quaxo

Rolofak adunabi ye, Rase quema Lbvazig arodi ; Mo.xati H o hyka Fagiva myne quidoxo Aukava i n Onfa yani moxarico, Pangdo Spulza Jor i lor ixa mugaro ya zaspor Alsiva y iva l ponbine Kazeb re linthvath.

Translation: Relieve us speedily, or we per­ish; for the enemy has been recnforced, and our provisions are nearly expended.

" T o exercise the English scholar " B l a i r also offers the following example of " plain ciphering," without the key or translation. T h i s cipher employs a methodized alphabet, i n which each number fixedly signifies but one letter. C a n you read the message, and reconstruct the alphabet?

C I P H E R No. 24 (Wil l iam B l a i r ) . 39. 38,31,21,35. 35, 14,20, 1 8 , 2 1 , 1 9 , 2 0 , 3 s , 34. 2 0 , 3 8 , 3 9 , 1 9 - 3 2 , 3 5 , 3 1 , 1 8 , 3 5 , 1 8 . 22, 39, 20, 38. 13, 31 , 14, 24. 20, 38, 39, 14, 37, 1 9 . 3 1 , 1 9 . 2 0 , 1 5 . 2 0 , 3 8 , 3 5 . 1 3 , 3 1 , 1 4 , 3 1 , 37, 39, 14, 37- 15, 36. 20, 38, 35. 31 , 36, 36, 31, 39, 18. 18, 35, 17, 21, 39, 19, 39, 20, 35. 36, 15, 18. 24, 15, 21. 20, 15. I I , 14, 15, 22. 18, 35, 13, 35, 13, 32, 35, i8- 20, 38, 31 , 20. I S , 14. 14, 15- 31 , 33, 33, 15, 21, 14, 20. 24, I S , 21. 36, 31 , 39, 13. 20, I S - 13, 35, 35, 20.

13, 35- 3 1 , 20. 14, 39, 14, 35. 20, I S , 13, I S , 18, 18, 15, 22, 19. 14, 39, 37, 38, 20. 36, 13, 18. 22, 35. 13, 21, 19, 20. 14, 15, 20. 14, 15,22. 3 4 , 3 5 , 1 2 , 3 1 , 2 4 . 2 0 , 3 8 , 3 5 . 19 ,21 , 18, i 6 , 18, 39, 25, 35. 15, 36. 20, 38, 35- 33, 31 , 19, 20, 12, 35. 22, 38, 35, 14- 20, 38, 39, 14,37,19. 3 1 , 1 8 , 3 5 . 3 9 , 2 1 , 1 9 , 2 0 . 18,39, 16, 35- 36, 15, 18. 35, 23, 35, 33, 21, 20, 39, I S , 14-

T h e translation of cipher No. 2 1 , pub­lished last week, is as follows: " T h e crypt is a form of cipher employing a method of simple literal substitution." W i t h its common, short words this should have been easy. D i d you get i t?

T h e two-alphabet principle involved in the autokey method outlined last week, and published here for the first time, can be used effectively against other important types of autokey ciphers, as we may later have opportunity to demonstrate. T h e re­current group 27-27-31-11, at the interval 13, was a ready clew in last week's ex­ample. No. 22, which used a reversed 2 6=/4 . . . i—Z alphabet. T h e mes­sage: " There is a skeleton in every house, and every family of respectability has its family ghost."

Coming now to the code messages pub­lished in the A p r i l 23 issue. No. i conveyed the following information enciphered with the key, 05175 49915 34073:

T h e crew of a Cantonese (Canton -ese) gunboat (gun boat) rebelled to-day and shelled Shanghai while attempting to bom­bard the arsenal one mile south of the city.

Code message No. 2, as follows, was en­ciphered with the key 12052:

We have discovered an underground (under ground) vault near the center of the island filled with pirates' treasure.

E a c h two-letter syllable in No. 3 repre­sented two figures according to the follow­ing table, where MU, for example, equals 4g (45 plus 4 ) ; and so on.

00 05 10 15 20 25 30 35 Consonants: B C D F G H J K 40 45 50 55 60 6s 70 75 80 85 90 95

L M N P R S T V W X Y Z 00 01 02 03 04

Vowels: A E I O U

Translat ing the code words into code numbers, 49915 34428 09955 • • -and these, in turn, into their proper vocabu-

4 8 0 F L Y N N ' S W E E K L Y

lary terms, reveals the message: " United Products has declared the regular quarterly dividend of two dollars."

Challenge cipher No. 12 (Fletcher P r a t t ) , published in the issue of A p r i l 16, used the figures 2 and 3 for A; 4 and 5 for E; and 6, 7, 8, g, for the word-space. A n y other letter was represented by the three letters next following it in the alphabet, and by itself, according to its occurrence in the message.

T h u s , O is substitute for the first L i n the message; N, for the second L ; M, for the th ird; and L itself for the fourth; this order being repeated ' a s many times as necessary. Here is a sample of the enci-pherment, and its translation in f u l l :

S 4 U V R Q3ONB 6 L 6 I K P G g W K . . . P E R S O N A L L V - I - F I N D - T H . . .

Personally I fmd the work of solving cryp­tograms insuperable; but I . enjoy designing them, and flatter myself that this one wi l l offer such difficulty to your solvers that none w i l l earn the year's subscription to F L Y N N ' S I w i l l give to the first who succeeds in do­ing so.

T h i s cipher should be subject to resolu­tion by the use of alphabetical strips, or by " running down the alphabet"—see F L Y N N ' S W E E K L Y for November 13,

1926—determining the values of the figures by context. Should any award be made in this instance, it wi l l be in favor of the best solution submitted, as advised in the issue of .April 16, instead of the first solution, as stated in the cryptogram.

T h e following have submitted answers to

the first five of the weekly department c i ­phers, published i n the issues of M a r c h 5, 12, and 19:

James Olden, Medicine H a t , Alberta Can-. a d a ( 2 ) . ,

Everett E w i n g , Norfolk, Virginia ( 2 ) . Paul A . Napier, Louisville, Kentucky ( 2 - 4 ) . Simon Horwitz , Chicago, Illinois ( 2 ) . Leo Brewster Myers, St. Louis, Missouri

Wil l iam T . M c C a w , Cambridge, Massachu­setts ( 2 ) .

K . Davidson, Montreal, Quebec, Canada ( 3 - 4 ) .

Basi l J . Condon, Durham, North Carolina ( 3 -4)

M . Walker, Akron, Ohio ( 3 - 4 ) . Hugh B . Rossell, Washington, District of

Columbia ( 4 ) . Stephen Chrapek, South Bend, Indiana

( 3 - 4 ) . A . L . Tuttle, Brooklyn, New Y o r k ( 3 - 4 ) . Charles Cooley, Bronx, New Y o r k ( 4 ) . Donald S. Hopkins, Detroit, Michigan ( 4 ) . John Q. Boyer, Primrose," Baltimore,

Maryland ( 5 ) . Rufus T . Strohm, •' A r t y EsS,' ' Scranton,

Pennsylvania ( 5 ) . H . ' B . McPherrin, "Hercules ," Denve.,

Colorado ( 5 ) .

T h a t ' s i t , folks! Keep the answers com­ing. T h e more, the merrier! .And while you're at it, send along that cipher of yours—preferably with the solution—for other readers of the department to puzzle over.

A s a bit of advice on parting, don't fail to see next week's department. Among other things you wi l l find in it some new ciphers, and the full explanations to the B l a i r ciphers in this issue.

10 F W