SOLVING CIPHER SECRETS

Edited by M. E. Ohaver

"A CARRIER PIGEON FELL EXHAUSTED AT THEIR FEET." WHAT MESSAGE DOES IT BEAR. IN JULES VERNE'S IMMORTAL STORY?

ILLE, n. A system of bars, posedly impossible, or at least materially especially of wrought iron, retarded. forming an open work bar• Thus the use of a grille, for instance, at rier, large or small, as a a window, or in preparing a cryptogram, is high fence inclosing a pub• for the purpose of preventing surreptitious lic building or across a pas• access to whatever lies beyond. And in this sageway, or the grating of a window. sense Webster's definition is as nicely suited {Webster.) to cryptography as to the intended meaning, This is the generally accepted meaning of since the grille is an open work barrier in the word grille. But to the cryptographer both cases. it takes on an added significance in that it Of grille ciphers there are many. The has been found convenient, because of a cer• invention of the original grille is attributed tain resemblance, to use the same term in to Jerome Cardan, the celebrated Italian designating the apparatus used in accom• physician and mathematician of the six• plishing certain types of ciphers. teenth century. And the simple grille de• The grille of cryptography, also com• scribed in this author's works will be treat• monly called a lattice or grating, is made ed in some detail in a later article. from any suitable flat material, as metallic An ingenious cipher derived from the plate, parchment, cardboard, or even paper, grille is said to have been used by the Ger• pierced with openings. mans during the World War. But probably The process of enciphering with a grille the most famous of the true grilles, and the varies with different types. But in every subject of this article, is that perfected in well known cipher of this kind the signifi• 1881 by Eduard B. Fleissner von Wostro- cant letters of the message are written witz, Austrian colonel, and author of a work through the openings or interstices of the on ciphers entitled, " Handhiic'i der Kryp- grille, the letters, letter groups, or words, tograpltie," published at Wien in the same thus being broken up from their original year. arrangement. Fictionists have had their fling at grille The key to a grille cipher is the disposi• ciphers. Honore de Balzac used a form of tion or arrangement of these openings, with• the original grille in 1881 in his " Histoire out knowledge of which any unauthorized des Trieze "—The Thirteen. Foe mentions reading of an enciphered message is sup• it. And to Jules Verne's story, " Mathais 634 FLYNN'S

Sandorf," first published in 1885, the world To begin, then, this cipher is of the trans• is indebted for an example of Fleissner's position class, the letters retaining their grille. original values, being changed only in their Verne was the author of numerous tales of relative order. This transposition is ef• extravagant voyage and adventure. This fected by means of the grille, which, in its author's was the peculiar genius of inter• most usual form, operates upon a square weaving scientific fact with fiction, yet with of letters consisting of an even number a skill that lent his narratives all the plausi• of rows and columns. bility of truth. This even number may be 2, 4, 6, 8, 10, And Verne, too, was one of the first writ• or any other even number whatsoever. ers to realize the value of ciphers in fiction. Suppose for illustrative purposes a square Solving Cipher Secrets for June 6 has al• of 6 rows and columns, having a capacity ready dealt with his use of the Gronsfeld of (6x6=) 36 letters, be selected. cipher; and this exposition will similarly The preparation of the grille consists of include his use of the Fleissner grille in determining the locations of its openings, " Mathais Sandorf." the arrangement used being the key to the This story differs, however, from the ac• cipher. To do this it is first required to customed Verne yarn. It tells no tale of a divide the square into four equal smaller mechanical monster of the skies or of the squares, as indicated in the subjoined dia• deep. Nor yet of a delving into the bowels gram by the Roman numerals I, II, III, of the earth, or of an interplanetary flight and IV, and then to number the cells or through space. spaces of each of these four squares in an A more usual narrative, this, being merely exactly similar manner, also shown in the the relation of a series of adventures, strung drawing. on the thread of governmental intrigue. The story opens on the eighteenth day of May, 1867, which finds two penniless ad• I venturers wandering aimlessly about 1 Z I-* Trieste, the capital city of Illyria. 3 In due course they ascend the slopes of 4 the Karst hills, and find themselves eventu• ally in an inclosure, formerly a cemetery. 8 6N Here an exhausted carrier pigeon falls al• 7 9 most at their feet. Concealed under its NO ON 9 wing they discover a cipher message, of I which one of them, scenting conspiracy, CO makes an exact copy. 9 They now revive the bird, and, climbing sH into a high church tower overlooking the Z T city, they release it and, watching the course of its flight, are fortunately able to observe its destination. m One of the adventurers now obtains em• In a grille of this size there are nine ployment at this place, obtains the key by numbers in each of these four smaller stealth, and deciphers the cryptogram. squares. Upon which hinges the remainder of the In grilles constructed on squares of 8, 10, story. or 12, there would be 16, 25, or 36 numbers, The cipher, as it happens, is Fleissner's; respectively; and so on. and the key is one of the innumerable forms Now, for reasons that will soon be obvi• of the grille possible with this cipher. In ous, the number of apertures or windows order to make this more understandable in any grille of the type being described some knowledge of the structure and use of is always the same as the number of cells this cipher is necessary. in each of the four subdivisions of the larger SOLVING CIPHER SECRETS 635

square. In other words the number of French. Besides, Verne took the additional openings is equal to one-fourth of the num• but unavailing precaution, which we will ber of cells in the entire square. not, of writing his message backward before In the present instance, then, there must enciphering it. Here is Verne's message in be g openings. And having determined English: their number, it is now required to decide ALL IS READY. AT THE FIRST SIG• on their locations. NAL TH.Vr YOU SEND TO US FROM This may be done by selecting any de• TRIESTE. EVERY ONE WILL RISE TO- sired numbers in any of the squares, with r.F:THER FOR THE INDEPENDENCE OF the single restriction that each number he HUNGARY. used once, but once only. To encipher this message, place the grille Suppose that it is decided to use cells upon a piece of paper, with the marked edge 2, and g in square I: cells /, 5, and 7 in on the upper side.and at the top. It is con• square II; j, 4, and B, in square HI; and 6 venient to use paper ruled in squares of the in square IV; all of the numbers thus being same size as the subdivisions of the grille. used, but each one only once. This key, But this is not absolutely necessary, as the more conveniently expressed, could be space occupied by the grille may be out• written: lined on the paper with a pencil mark. 1: 2-Q. Now, taking the letters of the message II: 1-5-7. in their regular order, write the first letters HI: 5-4-8. IV: 6. through the openings of the grille, placing but one letter in each opening, and using If openings be now cut or punched in each opening once. In doing this the lines any desired flat material in accordance with of the grille must be taken in their order this key, indicating the front and top of the from top to bottom, and any openings in apparatus by some distinguishing mark, as the same line must be used in their order an A', or the word TOP, the completed grille from left to right. will appear as shown in the accompanying In the present case the first nine letters illustration. of the message, A-L-L-l-S-R-E-A-D, will, upon removal of the grille, be found written TOP on the paper in the following order: 0 0 0 0 A Z zT 0 / 0 0 S 0 /? £ 0 A

Incidentally, you may be interested to D know that the grille just constructed is iden• tical with that used by \'erne in his story. Now give the grille one-quarter of a com• The grille prepared, next let us proceed plete turn in a clockwise direction, so that to the manner of using it. And to demon• the marked edge will be at the right. Then, strate this phase of the cipher since we have placing it upon the same space of the paper, used Verne's grille, nothing could be more write the second group of nine letters, fitting than also to use that author's mes• Y-A-T-T-H-E-F-I-R. through the openings, sage. observing the same rule as before. 'I'he original of this is, of course, in Whereupon the first nine letters previ- 636 FLYNN'S ously written, together with the second nine* low, now completely fill the remaining just written—printed below in italics so that spaces of the square, you may readily observe their order—will stand as follows: // A 5 L A L

A L L T r Y K i A

y A O s S T 1 i/

5 r T R G £ H £ T R E H N E /V F A £• r A A I L D T R

/ D R Thus the first 36 letters of the message have been enciphered. Each additional 36 letters are now treated in an exactly similar Next, having given the grille another manner, until the entire message has been quarter turn, so that the marked edge will enciphered. be at the bottom, place it upon the same In the event that any message, or remain• space, and similarly write the third group der of a message, is less than the capacity of nine letters, S-T-S-I-G-N-A-L-T, through of the grille, it is necessary that all un• the openings. occupied spaces be filled in with nonsignifi• The eighteen letters previously written, cant letters. with the nine just written—again in italics To illustrate, take Verne's message. Alter —will, upon removal of the grille, be found having enciphered two squares of 36 letters thus: each, only 31 letters remained for his third square. Verne therefore filled in these five A L L remaining spaces with the nonessential let• ters, X-R-Z-A-H. .And we have used these r y 1 A same letters here, having prepared our translation of the same length as Verne's <5 5 T / original message, with this purpose in mind. It looks complicated, but, although it takes T R G E H a little time, it is really very simple. .As in dealing with all ciphers, you will find accu• A/ E r A racy a necessity. In many ways the grille is as fascinating as any cipher ever invented. /I 1 L D r R Took at the one we have been working with. The entire message, completely enci• Filially, giving the grille another quarter phered as explained above, will now be in turn, so that the marked edge is at the left. the following form:

H S L A L L D E T R O G T E H A E T Y Y I A R I T S U R N R E Y R I o s T I U E Y S I O T X C F N E R T s G E H E F O N R S D O Z O R E E E N F A G E T F: E O A F P H E T A L D T R W E I M L V H N U H N D

write the fourth group of letters, H-A-T-Y- Veme allowed his cipher to remain in O-U-S-E-N, through the openings as before. this arrangement by squares. This would, The nine letters last written, italicized be- of course, be strongly suggestive of its type. SOLVING CIPHER SECRETS 637

but it must be borne in mind that his cipher of certain longer words usually found in was transmitted by carrier pigeon, where military messages. But even with tliis hint, interception would be unlikely. those who are successful in solving these In modern practice, however, especially if ciphers will be doubly deserving of credit. the message were intended for telegraphic Many, including Verne himself, have con• transmission, it would be transcribed into sidered the Fleissner grille indecipherable groups of five letter as follows: without the key. And, in this connection, Verne's own words will be interesting. HASLA LTTYY lAOSS TIUTR SGEHE NENFA AILDT RLDET " It would seem," says this writer, " that RORIT SUREY SIOTE FONRS gratings offer the best and surest means of GETEE OWEIM LVGTE HAENR obtaining an indecipherable cipher. With• EYRIX CFNER DOZOR EAFPH out the grating the message will remain un• ETHNU HND read, but once this is obtained the mystery The recipient of this cryptogram, if he vanishes." possesses a similar grille, has only to re• Now a grille has already been defined as verse the process just described in order to a barrier against an intruder. And this is read it. true whether that sought after be gold, or He rewrites the cipher into squares of the words, or rubies. proper size, most easily accomplished on But there are, nevertheless, certain dif• paper especially ruled for the purpose, and ferences in grilles. then applies the grille, reading the concealed For instance, consider a grille as at a message directly through the openings, door or window. Here if skill avails not a without any further manipulation. thief to gain entrance, he may still resort So much for the structure and use of the to violence, break through, and steal away Fleissner grille. In next Solving Cipher the treasures that may lie within. Secrets, besides some unusual facts about Not so with the grille cryptographic. this cipher, vve expect to explain a method For with this, if one lacks skill, force can of solving it. Appended, however, you will avail nothing. find two Fleissner ciphers to engage your Indeed, if the very elements were to rage interest in the interim. forever in all their fury at the riddle im• Concerning these ciphers, as to the sizes posed by this frail obstacle, its secret must of the grilles employed, or the arrangement still easily remain secure. of their openings, we are saying nothing. Here is a battle where force plays no These things, along with a method of solv• part, and wits play all. ing the cipher, are left for you to discover. Skill, properly directed, can certainly Neither have we anything to say of the prevail over this barrier. messages that these ciphers convey, with Can voii surmount it?

CIPHER No. I (Fleissner grille). ETOUU REFEX RNAIT HINAO DODUW SATOM NAARE MNLDI SETNI SENSF OARAT DNSUO PNDCC REMPE EEVUO IRWEE RHRTE HIONN UMDUS RTSEY TRVVES LZW.

CIPHER No. 2 (Fleissner grille). EANYE MBFRE RYEAP STOIM NLMOA RAKTP TEHHN WSRIE SSIST TRATS ATOTD ENANE CRKSG ETAHA RNDTE TSEOH OFUIF NSTAY ENNDT DHIHO UINUF SNANA TNDGN DFRWR YEIFD TAYRN EWINH DOOIF CHOUB NEEHR FUONC WRIDE RMEEM LIDDC LNIAG NNREN ETOHT SACAH NY. the exception that, in view of Colonel Fleiss• SPECIAL EXTRA! ner's army service, you might find that we " Noted bank robber traps himself with have made them of a military nature. cipher message! If this be true, besides the shorter con• " Buy a paper! Extra.'" nectives common to almost every variety of That the newsboys may soon actually writing, the reader may suspect the presence be crying this, and that FLYNN'S cipher ! 638 FLYNN'S fans may be instrumental in bringing it cial history; and one which, though not in• about, are not at all extravagant flights decipherable, should provide you with an of the fancy. interesting period of study. For a police official of a certain Western DEAR SIR: State has sent us a curious piece of writ• We have become interested in FLYNN'S ing, believed to be a cipher, taken from the magazine and especially in the cipher depart• person of a prisoner now jailed in his city, ment, and have resolved to send in for your awaiting trial for supposed bank robbery. approval a noted cipher which we have known The prisoner in question has a police in our family for a good many years. It was originally an old-time police cipher, record in three penal institutions. And the and we greatly doubt if there is any one writing, which may give a line on the move• living to-day who knows it except in our ments of this prisoner, was done with pencil family. H. J. LOTUS. upon a small piece of heavy brown paper. Chico, Calif. If any of you succeed in making any• CIPHER No. 4. thing out of this, communicate with us with• PGSJQWOJEFWIGDQN out delay, and your findings will be for• LYIHKTWROJJXDFHY warded to the above mentioned official im• WJQNSLPMWY. mediately. Next you will be given another chance at Here is the supposed cipher: a cipher written with a different manipula• m. B.D. C. fA I'/zTl. DO tion of the same key as was used with the fourth challenge cipher in FLYNN'S for YA, s/aL y June 27. U. •BA.%n. x'A-R.i.o.%w. This cipher really offers no great difficulty of solution. And, solving it, you should be FQ. 3'AAB. DC. I/4I.D.C. able to turn to the other cipher just men• Di. H. 2'AD.C. D.l. tioned, and penetrate its mystery also.

V. 3/zD.C.B. DEAR SIR: I am peeved, shocked, and disgruntled, be• WB. 3/il.D. 5 A.B.D. 2L. D.D. cause your " fans" will not admit that my '• cipher " is unsolvable. Until it is done I WOS. WIl. R.T/sH- l/aH.D. 1 D. shall, vehemently or otherwise, claim that no H.H.M. I'AXOYI. D.C. I'/xi.D.C. human being can solve it. In the event that the previous one was P.B. 1/2 B.l. D.C. I.R.-2/2L.D.O. overlooked, here is another one, just as sim• ple as I can make it. Go to it! CH. 4. LOW.D.0.^30". Just imagine that this message would be invaluable information to the government, and : solve it, or give it up. J. C. BELL. Cleveland, Ohio.

1 CIPHER No. s. 30-7-10-9-47-5-0-24-7-12-11-22-14-0-53-52-0- V. A.B.D. ff»^»lU:S 42-21-40-22-50-4-37-16-18-7-0-54-33-35-34- 35-T2-I4-I0-0-39-21-51-6-55-12-0-36-23-31- V.C. 11,5 A.B.D. 2.D.D.D. 10-48-36-28-22-27-16-0-63-14-52-51-72-29-0- 55-6-34-17-33-15-61-16-31-20-0-21-20-55-12-, TR. 4.H. D.C. %H. 0-82-39-73-47-59-30-62-13-0-27-26-48-22-17- 9-0-32-21-67-19-39-28-78-36-0-80-31-28-11- P. 0. 3/al.D.' Wil l^R 1 lA D 44-33-50-12-0-55-10-58-41-56-55-90-45-0-56- V. 3/2 1.D. lA.B. T 5 ah D. 8 £ 33-30-29-73-31-0-87-38-25-14-44-18-52-7-0- 68-23-24-7-53-42-0-47-26-18-17-69-46-75-71- 0-107-58-101-100-80-37-0-69-26-111-64-64- 8 in £ 0 1}^ bl 26- 0-55-10-78-49-0-II1-96-61-32-35-12-39- 27- 5S-13-O-S9-36-43-31-0-38-15-22-21-47-1I- De Z'/zJ. J> 0 72-27-36-18-32-6-60-17-15-11-79-32-89-53- 50-35-80-35-61-12-22-11-47-26-32-19-70-25- Now for another cipher, not so serious 62-45-0- as the above, perhaps, but still with an offi• 33-14-40-11-103-86-53-27-0- SOLVING CIPHER SECRETS 639

That the simple substitution cipher is cer• in possession of the key, which is numerical, tainly decipherable, given sufficient material can locate these significant letters in a few in the same key, has already been demon• minutes. strated. To solve it without the key, however, To make this cipher of any value among is a different proposition. the initiated, then, it would seem necessary CIPHER No. 7. to modify its appearance, to camouflage it, DE.AR PARTNER: in other words, so that it might be able to It would ruin our other wells or take quick• pass itself off as something other than its ly from the value of the bad one. It all real self. keeps on getting worse and, back of the cer• For e.xample, the following cipher from tain result, can, in general, be acknowledged a failure. Thomas F. Taylor, Brooks Field, San An• When you consider candidly that annually tonio, Texas, might get by an unsuspecting every dollar that by means of other people eye as an order, bill, or memorandum for we coined. It Immediately stops every move, some lumber. almost, in fact, effectively putting us out of doing something or other. Could it get by yours? All the investors have become impatient. CIPHER No. 6. When the attempt has entirely been immersed, 1 x3 13 DCS. IS ft. long; s pes. 22 ft. long we will buy up the most impatient at every 5x4 5 " 12 " •• 6 " 20 " •• reasonable opportunity. By all means stop 7x9 5 • i9 •• •• worrying. 2 X 4 5 " i3 " " do. 14 " " We differ on the other ways of effecting a 6 X 9 23 " 5 •• •• ^ pes, i4 " •• cleanup. Cold weather prevents buying the 4 X 3 8 " 20 *' " do. s " '• entire normal second field. Accordingly I will 3 X 2 15 " 20 " learn when I can get aggregate Information 8 X 9 I •• 25 •* '• do. 4 •• •' valuing it. Yet the lease was sold before clos• ing yesterday. Ciphers are infinite in their variety. And Am using corner lot where our old office the variations possible in any particular was for storehouse. Write or telegraph every• system are often so numerous as also to be thing Important and don't forget once in practically unlimited. awhile when puzzled and timid, strike hard. Your partner. Thus it is possible for one to know all JACK. about the construction of a cipher, but, without the special key, still be unable to Mr. Crawford also inclosed his method • solve it. of solving Nihilist ciphers, similar to that The next cipher, submitted by Jack described in FLYNN'S for October 10. As to Crawford, Los Angeles, California, is one the above cipher, he says he will take his of this kind. Only certain letters of certain hat off to any one who can decipher it. words have any significance here. Any one Must he doff it to you? DE ROHAN CIPHER SOLVED If you endeavored to solve the De Rohan These four words show that T, G, W, L, cipher—No. i in FLYNN'S for October 31 — H, and /, have been used as substitutes for along the lines suggested, you no doubt A, E, H, I, S, and T, respectively. Substi• eventually hit upon the values the,is, he,and tute these values throughout the cipher, and has, for groups i, 3, 5, and 6, respectively. the result is shown at (2):

(1) JWG DULHXCGU LH AGTA. WG WTH JXMA CXJWI.CZ (2) The is e— is —ea—, he has t thi- (3) The prisoner is dead, he has told nothing

There might be, of course, other short Proceeding then by the method detailed words that would satisfy the requirements in FLYNN'S for May 16, and the remainder of only these four groups, but it is highly of the cryptogram, as shown in line (3), improbable that any other values would also should have been deciphered without any satisfy the conditions of the remaining difficulty groups of the cipher. The original cryptogram in French can 640 FLYNN'S now be read, even u only out of curiosity, this cipher should have been sufficient to since it contains but one character—F, in show that Roman letters were used for the group 4—not found in the English, and former, and Italics for the latter. it takes no great stretch of the imagination Transcribing the cipher in terms of a to see that this must be the substitue for and b, dividing into groups of five, and sub• M. Here is the French: LE PRISON- stituting from the billteral alphabet, cipher NIER EST MORT, IL N'A RIEN DIT. No. 2 lines up thus:

To make this record complete, we now (1) ^bme AonbtfnMy veracious writer etc. append the De Rohan alphabet, recon• (2) baab aaabbbaaba aaabaabab abaaba etc. structed in so far as is possible from this (3) baaba aabbb aabaa aabaa babab aaba— etc. (4) T H E E X (E) etc. message. The two cipher characters Z and IF, in italics, are not a part of the original Completely deciphered, the internal or alphabet, having been used in the English infolded writing is: THE EXECU• for G and H, two letters not occurring in TIONER DECLARED AFTERWARDS the French. ON HIS O.ATH THAT SUCH OCCUR-

Normal ABCDEFGHIJKLMN OPQ R STUVWXYZ Cipher: T AG — XiKL MY C XD — U H J

The shorter a cipher of this type, the RENTES WERE EXTREMELY RARE. more difficult becomes the solution. How• It is not necessary, however, to have ever, many short specimens, such as the knowledge of Bacon's system in order to above, can often be read at sight. The No. solve this cipher. .Any one attempting to 4 cipher in the September 12 issue was an solve it without this information would soon example of this. Several fans wrote us that note the repetition of certain arrangements they solved this cipher at sight, and there of Roman and Italic letters by fives. And can be no doubt that many also similarly knowing that groups of at least five charac• succeeded in solving the De Rohan cipher. ters, each capable of two differences, would It is conceivable, though that even a sim• be needed to provide substitutes for all ple substitution cipher can be indecipher• the letters of the alphabet, it would only be able. This would be when the message was required to transcribe the characters in a of only two or three words, and written manner similar to line (4) above, when the in a mixed alphabet, where the identity of cryptogram could be solved as a simple sub• no character depends upon any ot^ier. stitution cipher. Now for a whack at No. 2, •^'hich, as From this it musfnot be inferred that many of you probably inferred, was writ• all Bacon biliteral ciphers are easy of solu• ten in Bacon's billteral cipher, described tion. In the two examples offered in the in FLYNN'S for April 25. April 25 and October 31 issues, this cipher Since in the biliteral alphabet the a char• was presented in its simplest form. acters may be expected to outnumber the b And these must be considered as only characters about two to one, a glance at paving the way for more complex varieties.

10 F W