Compete to crack secrets lost to history—for fun, clout, and (no) profit
| Status | Meaning |
|---|---|
| DEAD_END | A proper bounded attack produced a documented negative |
| MECHANISM_CLOSED_SOURCE_BOUNDED | The mechanism or reading is secure within explicit physical-source limits, without silently upgrading the underlying source |
| NEW_SOLUTION | This project independently produced a new, defensible ciphertext-to-plaintext solution for the registered target |
| PLAINTEXT_FOUND | A contemporary clear copy or translation supplied the content; the cipher was not broken |
| PRIOR_SOLUTION | An equivalent cryptanalytic solution was already available |
| SOURCE_LIMIT_CLOSED | The source boundary was controlled as far as the evidence permits, with no defensible complete plaintext or predictive key |
| SYSTEM_RECOVERED | A lost key, alphabet, phase, or mechanism was reconstructed using historically known material |
| TRIAGED_OUT | The target was deliberately closed as nondiscriminating or not worth further attack |
| ACTIVE | Currently being attacked without a substantive result yet |
| GATED | Blocked on sources, images, transcription, or controls |
| NEEDS_REVIEW | Legacy record requires human classification |
| PARTIAL | Substantial original result, but the registered target's meaningful reading or mechanism remains incomplete |
| PARTIAL_CRACK | A mechanically controlled fragment survives, but the registered postcard cluster does not have a complete reading |
| PAUSED | Intentionally stopped but resumable |
| QUEUED | Valid target prepared but not yet attacked |
| SOURCE_FREEZE_ATTACK_BARRED | Source preparation exists, but the predeclared release conditions were not met and no attack is authorized |
| Open problems | 74 |
| Closed problems | 165 |
| Total | 239 |
One number identifies a problem or related correspondence series. Its individual messages and repeated attempts are not extra problems. Partial readings and documented dead ends remain in the catalogue; they do not count as new solutions.
Each has a problem page and a separate solution. Some readings retain damaged or uncertain characters; the solution records their extent and limits.
| # | Date | Problem | How it was cracked |
|---|---|---|---|
| 14 | 19 March 1863 | Barney–Mallory Confederate Code A Confederate Navy report printed in the Official Records with eighteen words replaced by number triples. No key or corresponding plaintext survives in the archives. | Solution 14-1by @offgramercyContemporary letters named the method. The work was finding the exact printing. |
| 19 | 4 Dec 1861 (catalogue); probably 1862 | Bascom–Milroy Route Telegram A 79-token Union telegram from Bascom to Milroy preserves a military dispatch in scrambled ordinary words; the catalogued year conflicts with contextual dating. | Solution 19-1by @offgramercySuccessful project decipherment; first-ever publication priority remains unresolved after a bounded prior-solution search. |
| 24 | 23 December 1863 - 20 January 1864 | De Leon’s Lost Symbol Alphabet Three passages of De Leon’s despatches preserve geometric symbols; no alphabet key was located in the checked archives. | Solution 24-1by @offgramercyOne cipher word repeats its symbols in a shape only one English word fits. |
| 50 | 19 September 1864 | TEL474 – Sheldon–Eckert Fortress Monroe Ledger Forty-nine words entered in a Fort Monroe telegraph ledger on 19 September 1864, with nothing on the page marking which of them carry a hidden meaning. No clear copy, translation or prior reading is on record. | Solution 50-1by @offgramercyTelling the substituted cells from the plain ones, then a surviving key book. |
| 84 | 3 March 1865 | TEL784, Fort Monroe to City Point An EC25 telegram entered at Fort Monroe on 3 March 1865 is addressed in clear to S. H. Beckwith at City Point, but selected ordinary-looking words conceal its time, addressee, ranks, punctuation, phrases, and signature. | Solution 84-1by @offgramercy |
| 85 | 2 November 1864 | TEL513, Army of the James Artillery Return An Army of the James telegram entered at Fort Monroe on 2 November 1864 mixes ordinary artillery terms with innocent-looking code words across a five-battery return. Which cells are coded, and can every payload cell be read without borrowing wording from the adjacent request? | Solution 85-1by @offgramercy |
| 86 | 1 November 1864 | TEL511, Army of the James Best Batteries An Army of the James telegram of 1 November 1864 mixes ordinary battery descriptions with innocent-looking code words in a list of its five best batteries. Which cells are coded, and can every content cell be read without borrowing from the adjacent message? | Solution 86-1by @offgramercy |
| 87 | 5 November 1864 | TEL523, Fort Monroe Transport Report A Fort Monroe telegram of 5 November 1864 reports artillery horses, departing infantry, a disabled transport, and travel to Baltimore. Which ordinary-looking words are code, and can every payload cell be read without borrowing wording from related TEL522 traffic? | Solution 87-1by @offgramercy |
| 88 | 4 November 1864 | TEL518, New York Transportation Query A short telegram sent from New York to George D. Sheldon at Fort Monroe on 4 November 1864 hides a transportation query among ordinary-looking words. Which cells are coded, and can every payload cell be read without borrowing wording from the same-day answer TEL519? | Solution 88-1by @offgramercy |
| 89 | 6 November 1864 | TEL525, Fort Monroe Embarkation Outcome A Fort Monroe telegram of 6 November 1864 reports who supervised an urgent embarkation, how many troops and batteries departed, and the vessel roster. Which ordinary-looking words are code, and can every payload cell be read without borrowing wording from a same-event report? | Solution 89-1by @offgramercy |
| 91 | 1909 | Ben Russel Postcard [en] A 1909 postcard to Ben Russel mixes letters and digits in a private message. What does it say? | Solution 91-1by @offgramercy |
| 102 | 1911 | Jack and M. Jallett Postcard [en] A 1911 postcard from Jack to M. Jallett contains a backward-looking message field. What does it say? | Solution 102-1by @offgramercy |
| 103 | 1904 | Nan's Dorchester Postcard [en] A 1904 postcard from Dorchester signed Nan mixes letters with unfamiliar signs. What does the private note say? | Solution 103-1by @offgramercy |
| 111 | 1918 | Forest Beefe Postcard [en] A 1918 postcard signed Forest Beefe contains 22 unusual signs. What message do they form? | Solution 111-1by @offgramercy |
| 119 | Ralph Duckworth and Minnie Storey-Bates Correspondence [en] A large correspondence between Ralph Duckworth and Minnie Storey-Bates includes a dozen physical cards with private writing. What do the messages say? | Solution 119-1by @offgramercy | |
| 124 | 1906 | Charlie and Miss B. Correspondence [en] Two 1906 postcards from Charlie to Miss B. use the same set of private signs. What do the messages say? | Solution 124-1by @offgramercy |
| 125 | 1913 | Ezra and Leeah Doane Correspondence [en] Three postcards exchanged by Ezra and Leeah Doane in 1913 use rows of numbers. What do the messages say? | Solution 125-1by @offgramercy |
| 127 | Ray Bartley Postcard Packet [en] Five Iowa postcards sent to Ray Bartley between 1907 and 1908 combine ordinary prose with grids of private signs. What do the grids say? | Solution 127-1by @offgramercy | |
| 129 | Fritz Lehmann Correspondence [de] Eighteen German postcards to Fritz Lehmann include 12 private-message targets and six comparison cards. What do the private cards say? | Solution 129-1by @offgramercy | |
| 132 | 1907 | G. Groves Correspondence [en] Two 1907 postcards to G. Groves share the same hand, layout, and grouped marks. What do the messages say? | Solution 132-1by @offgramercy |
| 134 | Fritz Salmen and Frl. Braun Postcards [de] Thirty-four German postcards sent to Fritz Salmen and Frl. Braun use recurring number groups. What do the messages say? | Solution 134-1by @offgramercy | |
| 136 | Madeleine Boucheron Postcard [fr] A French postcard to Madeleine Boucheron contains a line of numbers followed by a short handwritten closing. What does it say? | Solution 136-1by @offgramercy | |
| 138 | O. Davy and Nell Correspondence [en] Two postcards to Nell from O. Davy contain rows of short and long marks. What do the messages say? | Solution 138-1by @offgramercy | |
| 141 | Annie Kepler Postcard [en] A postcard to Annie Kepler places a short private insert inside an ordinary party invitation. What does the insert say? | Solution 141-1by @offgramercy | |
| 142 | Thompson and Edwin H. Mallison Postcard [en] A postcard from Thompson to Edwin H. Mallison at the City Hotel contains seven rows of numbers and signs. What do they say? | Solution 142-1by @offgramercy | |
| 143 | E. R. Mobsby Postcards [en] Two postcards to Mrs. E. R. Mobsby use the same paired signs. What do the messages say? | Solution 143-1by @offgramercy | |
| 144 | Daphne Lidell Postcard [en] A postcard to Daphne Lidell in Clyde, Kansas, places 26 number tokens within ordinary social prose. What do the numbers say? | Solution 144-1by @offgramercy | |
| 145 | Frederica Clark Postcard [en] A postcard to Frederica Clark in Highland Park, New Jersey, contains 93 number tokens. What message do they form? | Solution 145-1by @offgramercy | |
| 149 | Sallie and Peggy Lewis Postcard [en] A portrait postcard associated with Sallie and Peggy Lewis carries a message made from short and long marks. What does it say? | Solution 149-1by @offgramercy | |
| 153 | Edna Mist Postcards [en] Two postcards to Edna Mist in Arkansas use the same private alphabet. What do the messages say? | Solution 153-1by @offgramercy | |
| 154 | Edith Elsworth Postcard [en] A California postcard to Edith Elsworth contains 79 private signs. What do they say? | Solution 154-1by @offgramercy | |
| 155 | Walt and Miss Nicholls Postcard [en] A London postcard from Walt to Miss Nicholls contains 148 numbers. What message do they form? | Solution 155-1by @offgramercy | |
| 156 | Abie and Henry Wulf Postcard [en] A postcard from Abie to Henry Wulf in Bennett, Iowa, carries 80 number tokens. What do they say? | Solution 156-1by @offgramercy | |
| 157 | Flossie and Jack Stalland Postcard [en] A postcard signed Flossie and addressed to Jack Stalland contains 37 numbered cells. What do they say? | Solution 157-1by @offgramercy | |
| 160 | Miss Adah Thompson Postcard [en] A postcard to Miss Adah Thompson in Streatham contains 58 geometric cells. What do they say? | Solution 160-1by @offgramercy | |
| 161 | 1903 | Miss Ramsay Postcard [en] A two-sided postcard mailed from Forres to Miss Ramsay in 1903 contains 150 short and long marks. What do they say? | Solution 161-1by @offgramercy |
| 163 | Grace Janson Valentine [en] An undated Valentine to Grace Janson in Bison, Kansas, contains 85 number tokens. What message do they form? | Solution 163-1by @offgramercy | |
| 167 | 1907 | K. Williams-Jones Postcard [en] A 1907 postcard to K. Williams-Jones contains 125 readable number values. What does the letter say? | Solution 167-1by @offgramercy |
Meaningful work remains, or the record still needs classification.
| # | Date | Problem | Status |
|---|---|---|---|
| 5 | 29 May 1887 - 7 May 1890 | Le Figaro MIG/BMA Numeric Ads Numeric cipher advertisements signed MIG and B.M.A. in Le Figaro's personal column, 147 ads between 1887 and 1890, full of conspicuous repeated digit runs. No reading of the numeric series has ever been accepted. | PAUSED |
| 7 | 1529 | Ghinucci–Worcester Letters pre 1800 · Latin context · Tudor correspondence · source gate Diplomatic letters associated with Girolamo Ghinucci, Bishop of Worcester, survive in BL Cotton Vespasian C IV, with target leaves and an annotated companion. | GATED |
| 8 | 1528 | Madrid–Ranzo Correspondence pre 1800 · Italian hypothesis · diplomatic correspondence · duplicate witnesses · negative trials Italian-context diplomatic records from 1528 in the BnF preserve unresolved cipher passages, including Ranzo correspondence and manuscript copies. | PAUSED |
| 11 | 13 July 1568 | Moray–Wood Edinburgh Letter pre 1800 · Scots hypothesis · Scottish regency · conditional partial reading · source conflict A partly enciphered letter from the Scottish regent Moray to John Wood survives in BL Add MS 32091 ff.213r–214v, catalogued 13 July 1568. | PARTIAL |
| 15 | 3 April 1916 | Tanaka ‘Rosamonde’ Telegram A 177-letter telegram of 3 April 1916 held in the Japanese diplomatic archives, addressed ROSAMONDE at Tokyo and signed only tanaka, catalogued as a message to Sun Yat-sen. No decode is on file. | PAUSED |
| 16 | summer/autumn 1936 | Spanish Strip Cipher Telegram A 142-token Spanish Civil War telegram from 1936, published as a challenge with zero recorded solves. Official hints point to the Spanish strip cipher family, with several homophones per column and alphabet variants. | PAUSED |
| 17 | 1941 | Barbarossa Enigma Residuals Eight short German Army Enigma messages from the 1941 Eastern Front, 522 cipher letters in all, that remain unbroken in the CryptoCellar collection. The machine model and rotor stock are known; the daily settings are not. | QUEUED |
| 18 | Reserved Catalogue Slot No cipher sits here: the candidate document, a short 1567 letter of Catherine de Médicis, was rejected before registration, and the number is kept only to preserve stable numbering. | NEEDS_ | |
| 20 | 29 December 1640 | Banér–Stålhandske Letter pre 1800 · German hypothesis · Thirty Years War · military correspondence · negative trials An intercepted letter from Johan Banér to Torsten Stålhandske, catalogued29December1640, survives as a copy in APUG568 f.239r–v with clear and cipher passages. | PAUSED |
| 21 | 31 July 1690 - 9 August 1690 | Castaignère Constantinople Dispatches Two enciphered dispatches from Versailles to Castaignère, the French ambassador at Constantinople, in 1690, written in a numeric word-code. A published partial reading covers roughly 85 percent of the tokens and openly invites completion. | PARTIAL |
| 28 | 1864-1865 | M618 Roll 19 Cipher-Telegram Census The Confederate War Department's surviving telegram files on NARA microfilm M618 hold cipher telegrams scattered among thousands of clear items, with no index of which items preserve raw cipher text. Roll 19 carries the late-war traffic. | PARTIAL |
| 29 | 22 January 1864 | Pickett–Seddon Petersburg Telegram A seven-line cipher telegram from Major General Pickett at Petersburg to Secretary of War Seddon, 22 January 1864: 150 cipher letters in 31 groups, one group visibly canceled, and no clear translation filed with it. | PARTIAL |
| 30 | 16 January 1864 | Pickett’s Petersburg Cipher Telegram A cipher telegram from Major General Pickett at Petersburg to Secretary of War Seddon in Richmond, 16 January 1864: 66 letters in 16 dash-separated groups, preserved in two exposures of the same leaf with no clear translation. | PARTIAL |
| 31 | 9 September 1863 | Jones’s Abingdon Cipher Telegram civil war A mixed telegram from Jones at Abingdon breaks into grouped cipher writing before returning to ordinary prose. | PAUSED |
| 33 | 22 October 1863 | Jones’s Cipher Reference Card An October 1863 telegram record of Major General Samuel Jones labeled Cypher in the Confederate register. The filmed packet holds only a publication-reference card; the cipher original is missing. | GATED |
| 34 | 5 December 1863 | Cobb’s Missing Undeciphered Message A December 1863 message of Major General Howell Cobb known only from a surviving reply, which says the preceding message was in cipher and could not be deciphered. The ciphertext itself is missing. | GATED |
| 41 | 13 March 1865 | Taylor’s Damaged Meridian Receipt civil war A damaged cipher telegram received from Lieutenant General Richard Taylor at Meridian, 13 March 1865: about fifty legible letters with separators on a noisy receipt, and a contemporary clear opening of a few words. | PARTIAL |
| 44 | 3 February 1864 - 6 April 1865 | Fort Monroe No. 1 Traffic Census civil war The Huntington Library's Fort Monroe telegraph books preserve 840 Union telegrams of 1864 and 1865, many recorded in cipher. Whether any cipher item lacks a surviving clear copy anywhere in the record was unknown. | PARTIAL |
| 46 | 25 April 1864 | TEL177, Eckert to Sheldon A coded telegram from Thomas Eckert in Washington to the cipher operator Sheldon at Fort Monroe, 25 April 1864, entered as 100 word cells in a ten-by-ten block. No clear copy accompanies it. | GATED |
| 52 | 8 December 1864 | TEL558 – Bermuda Hundred Traffic civil war · source dependency correction A coded telegram from the cipher operator Beckwith at Bermuda Hundred to Sheldon at Fort Monroe, 8 December 1864, entered as 63 word cells in a nine-by-seven block. | GATED |
| 57 | 14 January 1865 | TEL686, January 14 Morgan Telegram A 24-cell coded telegram from Morgan at Fort Monroe to Rawlins at City Point, 14 January 1865, closing a cluster of three short coded messages. | GATED |
| 62 | June 1862 | McClellan and Eckert Cipher Telegrams, June 1862 Coded Union telegrams of June 1862 between McClellan's headquarters and the War Department telegraph office, preserved in the Library of Congress. Which codebook copy and word assignments the operators used is not documented. | PARTIAL |
| 64 | 17 July 1862 | TEL293, Pope to McClellan A coded telegram from General Pope to General McClellan, 17 July 1862, entered as 81 body tokens in fourteen rows of six. The question is whether mechanics learned from related messages can read it without consulting its published clear. | PARTIAL |
| 66 | 1864 | Missing Plum Workbook William F. Friedman's collection records a Civil War telegraph workbook as Item 187, tied to the Plum and Stager tradition. Only six partial public PDFs are available; the complete copy-specific workbook has not been acquired. | GATED |
| 67 | c. 1861 - 1863 | Huntington Orphan Codebooks Three manuscript codebooks in the Huntington Library's telegraph collection: one unidentified, one of generals and places, and one whose catalogue identity looks wrong. None has a known message that uses it. | PARTIAL |
| 68 | 1 February 1862 - 1 August 1867 | Eckert Ledger Replay Repair Thirty-five Union telegraph ledgers at the Huntington Library, 11,208 images, whose digital records carry broken or missing child metadata. Messages cannot be cited reliably until each ledger's contents replay from its images. | PARTIAL |
| 70 | 1860s | NARA Union Traffic Discovery Pipeline NARA's Union telegraph collections, the M473 press copies and M504 unbound telegrams, run to hundreds of rolls with no message-level index. Finding the frame that holds a given telegram's clear copy is the problem. | PARTIAL |
| 71 | 13 June 1863 | Whiting’s Wilmington Cipher Telegram A telegram from General W. H. C. Whiting at Wilmington to Secretary of War James A. Seddon, 13 June 1863, alternates clear words with spaced lowercase cipher letters. Its key and encrypted wording are unknown. | GATED |
| 77 | 31 January 1864 | Polk’s Meridian Cipher Telegram civil war A mixed clear-and-cipher telegram from Polk to Seddon at Meridian contains three short encrypted passages. | PARTIAL |
| 78 | c. 1859 - 1863 | Bunch–Foreign Office Grouped Cryptograms Three photographed cryptograms associated with British consul Robert Bunch and the Foreign Office contain 90 four-letter groups, 360 letters in all. Their plaintexts, keys, and generating system are unknown. | GATED |
| 79 | November 1861 | Lyons November Cipher Sheet A November 1861 sheet carries twelve four-letter groups above a clear note to Lord Lyons saying its writer cannot make sense of the cipher. The writer, direction, key, mechanism, and plaintext remain unknown. | GATED |
| 80 | 1864 - 1865 | Hamilton Canada Orphan Traffic A Confederate State Department register headed “At Cassius F. Lee’s, Hamilton, Canada” has six remaining holder or alias lines for which no corresponding cipher traffic has been identified. | GATED |
| 81 | 9 November 1863 | Quintero–Benjamin Numeric Postscript Quintero’s 9 November 1863 dispatch to Benjamin ends with twenty-one three-digit groups beside a contemporary translation. Every group and aligned plaintext digraph is unique, so this specimen supplies no repeated mapping. | GATED |
| 82 | 19 March 1864 | Magruder–Taylor Missing Cipher Traffic On 19 March 1864 Richard Taylor reported that he could not decipher dispatches from John B. Magruder because he lacked Magruder’s key. The cipher bodies and contemporary clear copies are missing. | GATED |
| 83 | 7 - 17 February 1865 | TEL767–TEL768, Fort Monroe Dispatch Pair Two consecutive partly coded telegrams entered in the Huntington Fort Monroe telegraph book on 17 February 1865 have clear manuscript and printed counterparts. The content was never lost, but the EC25 copy does not identify coded versus literal words or its processing stage. | PARTIAL |
| 90 | 1861 | Bunch–Lyons Despatch, by 29 November 1861 By 29 November 1861, British consul Robert Bunch sent Lord Lyons a despatch explicitly described in official correspondence as being in cipher. The surviving official notes describe its interception and custody but do not reproduce the body. | GATED |
| 92 | Kottler and Frieß Correspondence [de] postcards A series of postcards exchanged by Kottler and Frieß includes one densely written private card. What can be read from it? | GATED | |
| 96 | Anna Tichá Postcard Group [und] postcards Twelve postcards to Anna Tichá appear related, and three contain a repeated ending. Can the private writing be understood? | GATED | |
| 98 | 1873 | George Furlong and Lizzie Postcard [und] postcards · no new reading · preserved research · private correspondence An 1873 postcard from George Furlong to his sister Lizzie contains six rows of grouped signs. What message do they carry? | PAUSED |
| 114 | 1918 | Bear Lake Postcard [und] postcards A 1918 Bear Lake postcard contains two columns of numbers beside an otherwise ordinary message. What do the columns represent? | PAUSED |
| 120 | Rollins Postcard Collection [und] postcards The Rollins collection holds about 2,000 postcards, including several cataloged as coded. Which cards contain private writing, and what do they say? | GATED | |
| 122 | Westmount and Sabourin Correspondence [fr] postcards The Westmount and Sabourin archive contains hundreds of postcards, including selected cards with private markings. What do those markings communicate? | GATED | |
| 130 | 1909 | Erna Garbe Postcards [de] postcards Four German postcards to Erna Garbe in 1909 contain three visibly different kinds of private writing. What can be read? | GATED |
| 135 | Hedwig Zipfel and Hugo Correspondence [de] postcards A postcard to Hedwig Zipfel belongs to a larger exchange with Hugo and shares features with 12 readable comparison cards. What does its private passage say? | PARTIAL_ | |
| 137 | Brühl Correspondence [de] postcards A remaining postcard from the Brühl correspondence has four readable cards from the same exchange for comparison. What can be recovered? | PARTIAL_ | |
| 139 | Miss J. Williams Postcards [und] postcards · no new reading · preserved research · private correspondence Three postcards to Miss J. Williams share the same hand, layout, and set of signs. What do they say? | PAUSED | |
| 140 | Gertrude Forrest Correspondence [und] postcards · partial reading · preserved research · private correspondence Two postcards to Gertrude Forrest contain private writing. What do they say? | PARTIAL | |
| 148 | Will and A. Russell Postcard [en] postcards A postcard from Will to A. Russell contains several chunks of altered lettering. What can be read? | PARTIAL_ | |
| 151 | Ernest and Amelia Letter [en] postcards A letter between Ernest and Amelia contains a body of 223 signs between an ordinary salutation and signoff. What does the body say? | PARTIAL_ | |
| 158 | Miss E. E. Edwards Postcard [und] postcards · no new reading · preserved research · private correspondence A postcard to Miss E. E. Edwards at Hartham Road contains 89 marked cells. What message do they carry? | PAUSED | |
| 211 | May Graham Postcard [und] postcards · partial reading · preserved research · private correspondence A postcard cataloged for May Braham may instead address May Graham. What can be established about its 12 marked rows? | PARTIAL | |
| 212 | Lawrence Shansbaugh Postcard [und] postcards · no new reading · preserved research · private correspondence A postcard associated with Lawrence Shansbaugh lacks a settled mapping between its two sides and the source records. What can be established? | PAUSED | |
| 218 | 22 October 1908 (provisional) | R. Easton Postcard [und] postcards · partial reading · preserved research · private correspondence A postcard sent to Miss R. Easton at Barnstaple contains a private message. What does it say? | PARTIAL |
| 219 | Brimble Postcard [und] postcards · partial reading · preserved research · private correspondence A California postal card addressed to the Brimble recipient contains a main message and detached writing. What do they say? | PARTIAL | |
| 220 | 1862-12-03 | Cox–Milroy Cipher Telegram [en] civil war · union · telegram · route cipher A multi-page Union dispatch to Milroy survives in route-cipher form with uncertain source and commencement details. | PAUSED |
| 221 | 1865-04-10 | Surget–Taylor Forwarded Exchange [en] civil war · confederate · telegram · compound message A Confederate exchange preserves two cipher units alongside related ordinary text in the outgoing record book. | PARTIAL |
| 222 | 1864-08-17 | Maury’s Courier Cipher [en] civil war · confederate · courier · telegram A short cipher passage appears in an outgoing Confederate courier dispatch. | PARTIAL |
| 223 | 1865-01-18 | Taylor’s January Telegram to Davis [en] civil war · confederate · telegram · prior publication A long Confederate cipher telegram from Taylor to Davis survives in the outgoing record book. | PARTIAL |
| 224 | 1865-01-23 | Surget’s Telegram to Martin [en] civil war · confederate · telegram · intelligence A Confederate intelligence telegram to Martin contains two encrypted blocks among ordinary instructions. | PARTIAL |
| 225 | 1864-06-13 | Biggs’s Fort Monroe Forwarding [en] civil war · union · telegram · compound message One Fort Monroe telegram entry contains two embedded dispatches concerning transport and bridging arrangements. | PARTIAL |
| 226 | 1861–65 diary; symbols undated | Allspaugh’s Diary Symbols [und] civil war · union · diary · symbols Geometric passages and annotations recur across diaries attributed to Union soldier Jacob Harrison Allspaugh. | PAUSED |
| 227 | Undated; Civil War attribution | Murdaugh’s Cipher Sheet and Table [und] civil war · confederate · navy · alphabet table Two Emory objects preserve a cipher-bearing sheet and an associated alphabet table attributed to Confederate naval use. | PAUSED |
| 228 | 1903-06 (reported) | Sophie Halbgebauer Postcard [und] postcards · partial reading · preserved research · private correspondence What does the private message on this postcard say? | PARTIAL |
| 229 | 1905 (reported) | Miss Appleton Postcard [und] postcards · no new reading · preserved research · private correspondence What does the private message on this postcard say? | PAUSED |
| 230 | 1935-10-29 (reported) | Philip Chapman Postcard [und] postcards · partial reading · preserved research · private correspondence What does the private message on this postcard say? | PARTIAL |
| 231 | 1912-06-03 (reported) | Ern and Miss Riggs Postcards [und] postcards · partial reading · preserved research · private correspondence Two postcards preserved with the Ern and Miss Riggs correspondence contain private messages. What do they say? | PARTIAL |
| 232 | 1874-06-22 (reported) | Cresson Family Postcards [und] postcards · no new reading · preserved research · private correspondence Several nineteenth-century Cresson family postcards contain concealed messages. What do they say, and which belong together? | QUEUED |
| 233 | Dates vary; some undated | French Numeric Postcards (Provisional) [und] postcards · French context · scope exception · provisional collection · partial reading Seven privately written numeric postcards are preserved together. What do their messages say, and which belong to the same correspondence? | PARTIAL |
| 234 | 1648-11-06 (catalogue) | Craven–Rupert Hague Letter [und] pre 1800 · English context · royalist correspondence · unresolved target · negative trials A letter catalogued as Craven to Prince Rupert, The Hague, 6 November 1648, survives in BL Add MS 18982 ff. 134r–135v with mixed clear and cipher passages. | PAUSED |
| 235 | 1619-12-22 (catalogue) | Ferdinand’s Bonn Letter [und] pre 1800 · German context · diplomatic letter · numerical cipher · source uncertainty · short fragments only A long diplomatic letter combines dense numerical passages, graphic marks and German writing. Several photographs preserve continuations and marginal additions whose relationship to the main text must be kept explicit. | PAUSED |
| 236 | 1646-05-13 (catalogue) | Intercepted Letter to Charles I [und] pre 1800 · English context · intercepted letter · numerical cipher · negative direct trials An intercepted royalist letter in the Weckherlin papers has dense numerical passages and an enciphered signature. The catalogue describes it as largely undecoded; its sender is unidentified. | PAUSED |
| 237 | 1782 and 1787 | De Swart’s Dutch Dispatches [und] pre 1800 · Dutch · diplomatic correspondence · decorated numbers · negative direct trials Two Dutch diplomatic records use decorated numerical groups. The marks can attach to different parts of a number, and some surviving photographs or transcript sections repeat material. | PAUSED |
| 238 | Undated; 1628 attribution unverified | German Correspondence in the Rusdorff Papers [und] undated carryover · German context · numerical cipher · negative direct trials · source uncertainty A German letter and short note in a shared archival packet contain numerical groups among ordinary writing. Their exact date and relationship are not securely established. | PAUSED |
| 239 | March–April 1624 | Rusdorff’s London Letters [la] pre 1800 · Latin · diplomatic correspondence · partial recovery · on page plaintext · source collation Latin diplomatic letters combine ordinary text with alphabetic runs. One letter carries marginal glosses and a long note; another contains both a covering letter and a separately dated formal enclosure. | PARTIAL |
Resolved, exhausted, or deliberately set aside.
| # | Date | Problem | Status |
|---|---|---|---|
| 1 | 25 January 1691 | Feuquières–Catinat Veillane Dispatch A 418-group French petit-chiffre order for a surprise attack on Veillane; large nomenclator searches produced no defensible plaintext or key. | DEAD_ |
| 2 | 30 May 1653 | Bordeaux–Brienne London Dispatch pre 1800 · French context · diplomatic correspondence · negative trials · source collation New source readings and corrected-input searches recovered no connected French; source and model limitations remain explicit. | DEAD_ |
| 3 | 15 September 1702 | Catinat–Zurlauben Letter of 1702 pre 1800 · method only negative A stronger search failed on released examples; the historical Catinat target remained unopened. | DEAD_ |
| 4 | 15 April 1542 | Farnese–Poggio Vatican Cipher An eight-page 1542 papal diplomatic nomenclator with no listed solve; three digit-only key families were tested and rejected, and no result can be verified without manuscript scans. | DEAD_ |
| 6 | December 1585 | Tempest–Barrett Intercepted Letters pre 1800 · French context · Elizabethan correspondence · bounded legacy negative The recorded attacks failed on no. 78; source boundaries and possible key sheets remain unresolved. | DEAD_ |
| 9 | 30 April 1779 | d’Estaing–Gérard Martinique Dispatch The full wording of both encrypted spans—216 number groups—was recovered from an archival clerk’s clear copy, while the numeric key remains unknown. | PLAINTEXT_ |
| 10 | 12 May 1657 | Le Tellier–Castelnau Letter pre 1800 · target facing witness exclusion An exact comparison rejects one corrected documentary witness under the fixed tested grammar; no plaintext or key was recovered. | DEAD_ |
| 12 | 1 September 1653 | Dutch Envoys–Boreel Code A 136-token First Anglo-Dutch War letter retired after the same text was found already printed in clear Dutch in the 1725 Verbael. | PRIOR_ |
| 13 | 4 July 1941 | HG Nord Truppenschlüssel Seven Seven 4 July 1941 Truppenschlüssel messages were withheld after a two-square solver recovered its solved control below chance. | DEAD_ |
| 14 | 19 March 1863 | Barney–Mallory Confederate Code Identifying Webster’s 1850 edition decoded 17 of 18 word coordinates mechanically; context and source evidence support guns for the defective final group. | NEW_ |
| 19 | 4 Dec 1861 (catalogue); probably 1862 | Bascom–Milroy Route Telegram civil war The route search recovered a coherent 68-word dispatch. Manuscript alternatives and the year remain qualified; publication priority is unresolved. | NEW_ |
| 22 | 11 January 1863 - 16 February 1864 | Slidell–Benjamin State Cipher The previously published running key WHERE LIBERTY DWELLS THERE IS MY COUNTRY was replayed over 1,666 letters in 69 passages across ten Confederate dispatches. | PRIOR_ |
| 23 | 28 June 1861 - 6 June 1863 | Mallory–North Cobb Dictionary Code Comparing 1,436 coded positions with Cobb’s 1856 dictionary repaired eight blank or incorrect words in letters whose plaintext had already been printed. | PRIOR_ |
| 24 | 23 December 1863 - 20 January 1864 | De Leon’s Lost Symbol Alphabet civil war The previously recovered core alphabet stands, with a revised interpretation of rare forms and a withdrawn copying-error claim. | NEW_ |
| 25 | 15 December 1864 | E. J. R. Nassau Cipher Letter Two manuscript copies pair cipher with contemporary interlinear plaintext; the project re-derived MORTONTBLEDSOE, but the key’s Rivers association was already published. | PRIOR_ |
| 26 | June 1864 | Hines’s Cowards Only Flee Dispatch A 36-segment, 824-letter audit reproduces the Hines–Seddon Vigenère reading, but both COWARDSONLYFLEE and a complete 1977 decipherment predate the project. | PRIOR_ |
| 27 | 1861 | Greenhow’s Symbol-Cipher Packet civil war The long letter and alphabet were already public, a proposed second cipher/plaintext pairing failed alignment, and only a tiny context-poor glyph tail remains. | PRIOR_ |
| 32 | 12 September 1863 | Jones’s Missing Four-Page Cipher The register records four cipher pages that disappeared before filming, while an Official Records clear supplies the message and leaves only source/key recovery open. | PLAINTEXT_ |
| 35 | 8 October 1864 | Maury’s Mobile Cipher Insertions A clear companion and COMPLETE VICTORY reproduce five encrypted name insertions 29/29, correcting ‘Old Kennelle’ to RED GAUNTLET. | SYSTEM_ |
| 36 | 21 October 1864 | Hood’s Vowel-Insertion Telegram Two full clerk interpretations describe Hood’s move toward the Tennessee River; the raw cipher is gone, leaving only a note that vowels were inserted. | PLAINTEXT_ |
| 37 | 22 October 1864 | Beauregard’s Publication-File Dispatch A reference card leads to the complete Official Records dispatch on Sherman and the Army of Tennessee, but the removed cipher sheet and key remain missing. | PLAINTEXT_ |
| 38 | 25 November 1864 | Jones’s Charleston Battery Request The filed clear asks that Browning’s battalion reinforce Charleston’s water defenses; no raw cipher survives to recover the key or mechanism. | PLAINTEXT_ |
| 39 | 17 January 1865 | Hardee’s Augusta Telegram to Seddon COMPLETE VICTORY and variant Beaufort reproduce ‘SEVENTY FIVE THOUSAND BALES OF COTTON DAMAGED’ 39/39 against an independent clear. | SYSTEM_ |
| 40 | 12 February 1865 | Hardee’s Orangeburg and Branchville Telegram COME RETRIBUTION decodes a route fragment containing SOUTH FORKS, but its first token reads CAPMER and still has no secure interpretation. | SYSTEM_ |
| 42 | 8 March 1865 | Kirby Smith’s Imperfect Decipherment The Official Records completes the clerk’s imperfect decipher at ‘sails on the 10th for Texas,’ but no raw cipher survives for key recovery. | PLAINTEXT_ |
| 43 | 20 February 1865 | Hoke’s Wilmington Telegram to Lee COME RETRIBUTION predicts the held-out DISPUTE span 7/7 and reconstructs all 34 encrypted letters; a clear companion means the result is system recovery. | SYSTEM_ |
| 45 | 22 April 1864 | TEL155, Meigs to Butler A complete NARA clear aligns all 60 cipher cells and preserves a high-quality No. 1 key-and-mechanics control, while closing plaintext novelty. | PLAINTEXT_ |
| 47 | 12 June 1864 | TEL387, Benham to the Army of the Potomac The Official Records supply Benham’s full pontoon-bridging message, yielding a 117-cell exact alignment retained as a carefully scoped No. 1 control. | PLAINTEXT_ |
| 48 | 24 July 1864 | TEL450 – Butler’s Headquarters to Biggs Butler’s known-clear request to Biggs helped identify the public No. 1 table family and seed the EC25 scanner, but not the physical operative copy. | PLAINTEXT_ |
| 49 | 25 July 1864 | TEL451 – Biggs’s Next-Day Reply Biggs’s reply to TEL450 has its own exact NARA clear and long traffic alignment, proving it is a distinct message rather than TEL450’s clear copy. | PLAINTEXT_ |
| 50 | 19 September 1864 | TEL474 – Sheldon–Eckert Fortress Monroe Ledger The project recovered all 49 cells of Webster’s order to arrange transport for 5,700 sick prisoners, with no prior exact reading found in the bounded audit. | NEW_ |
| 51 | 17 October 1864 | TEL497 – Curtin to Lincoln, Washington Relay Copy A pre-decode Official Records search found the exact Curtin-to-Lincoln plaintext, demonstrating the source gate while preventing a false novelty claim. | PLAINTEXT_ |
| 53 | 3 January 1865 | TEL625 – Morgan to Rawlins, 3 January 1865 A complete NARA clear fixed all 72 body cells and added Waldo→Thousand and Whig→Transportation to the public-position register. | PLAINTEXT_ |
| 54 | 13 January 1865 | TEL683 – Morgan to Rawlins, 13 January 1865 A clear-and-worksheet pair reconstructs the exact nine-column route, consuming every payload cell and reproducing all 47 transmitted tokens. | PLAINTEXT_ |
| 55 | 13 January 1865 | TEL684 – 26-Cell Morgan Telegram Official Records p.114 editorially preserves TEL684's content in a combined Morgan report, preempting novelty before any decoder exposure. | PLAINTEXT_ |
| 56 | 13 January 1865 | TEL685 – 24-Cell Morgan Telegram Official Records p.114 editorially preserves TEL685's content in the latter part of a combined Morgan report, preempting novelty before decode. | PLAINTEXT_ |
| 58 | 16 January 1865 | TEL695, Buckland to Butler Independent replay confirms five additional public EC45 positions from the full Huntington clear, raising the stable direct register to 325 of 1,220. | PLAINTEXT_ |
| 59 | 9 February 1865 | TEL759, Halleck to Grant The published 32-cell core and partly resolved four-cell relay prefix provide a same-page session control for TEL760 without proving shared operative state. | PLAINTEXT_ |
| 60 | 9 February 1865 | TEL760, Rucker to Ingalls A NARA manuscript supplies the complete Rucker-to-Ingalls plaintext and an exact 110-cell alignment covering quantities, transport inventory, and relay behavior. | PLAINTEXT_ |
| 61 | 15 March 1865 | TEL817, Gordon to Ord Distinctive visible phrases located Gordon’s exact plaintext in the Official Records before decoding, making this a source-search positive control. | PLAINTEXT_ |
| 63 | 1864 | Union Cipher Book No. 2, Two Huntington Copies An 87-frame comparison repaired two No. 2 codebook copies in detail but found no copy-state difference that unlocks an unknown telegram. | DEAD_ |
| 65 | 25 March 1863 - 10 July 1863 | Matching Serials in Two Union Ledgers The audit proved matching telegram numbers across EC23 and EC06 are ledger-local coincidences, leaving only one thin, low-value residual. | TRIAGED_ |
| 69 | 7 July 1864 | Dana–Stanton Seven-Column Route An exact 11×7 worksheet replay reproduces all 84 routed and check tokens, but the plaintext, indicators, and route were already public. | PRIOR_ |
| 72 | 8 November 1863 | Jones’s Narrows Cipher Telegram An exact M618 publication card routes the missing cipher original to a complete Official Records clear, closing N1 while leaving source and key recovery open. | PLAINTEXT_ |
| 73 | 20 November 1863 | Bragg’s Missionary Ridge Cipher Telegram A native M618 reference card points to the complete Official Records text, preempting plaintext novelty while the original cipher and mechanism remain absent. | PLAINTEXT_ |
| 74 | 2 - 4 June 1863 | Johnston’s Jackson Cipher Telegram A five-exposure M618 packet retains raw cipher spans, but an 1864 official pamphlet prints the complete clear and exposes a Cooper-versus-Seddon recipient variance. | PLAINTEXT_ |
| 75 | 28 June 1863 | Hill’s First Petersburg Cipher Telegram The first of two separately registered Hill telegrams shares a publication card whose complete Official Records clear closes N1; its raw cipher is absent. | PLAINTEXT_ |
| 76 | 28 June 1863 | Hill’s Second Petersburg Cipher Telegram The second Hill register row maps through the same two-telegram card to a distinct complete printed clear, while no raw cipher or key survives in M618. | PLAINTEXT_ |
| 84 | 3 March 1865 | TEL784, Fort Monroe to City Point All 98 payload cells are mechanically read as Ord's fraud-investigation report to Grant; bounded Rule 8 found no prior exact clear, and two public rows advance the register to 394. | NEW_ |
| 85 | 2 November 1864 | TEL513, Army of the James Artillery Return All 69 payload cells are mechanically read as a five-battery strength return; an independent audit found zero gaps, and Amos to New York advances the public register to 395. | NEW_ |
| 86 | 1 November 1864 | TEL511, Army of the James Best Batteries All 50 content cells are mechanically read as a five-battery ranking; an independent audit found zero gaps, and Negro to Artillery advances the public register to 396. | NEW_ |
| 87 | 5 November 1864 | TEL523, Fort Monroe Transport Report All 81 payload cells are mechanically read as the Fort Monroe transport report; an independent audit found zero gaps, and the five closing transfers add no public key row. | NEW_ |
| 88 | 4 November 1864 | TEL518, New York Transportation Query All 24 payload cells are mechanically read as a transportation query; an independent audit found zero gaps, and the exact stable/literal partition adds no public key row. | NEW_ |
| 89 | 6 November 1864 | TEL525, Fort Monroe Embarkation Outcome All 70 payload cells are mechanically read as an embarkation outcome report; an independent audit found zero gaps, and the exact evidence partition adds no public key row. | NEW_ |
| 91 | 1909 | Ben Russel Postcard [en] postcards The writing convention is established and more than 30 English words are readable. A few pale details remain uncertain because of the source image. | NEW_ |
| 93 | 1907 | Daisy and May Flegg Postcard [en] postcards The block is ordinary English written upside down relative to the card. Independent readings agree on the message apart from minor handwriting uncertainties. | PLAINTEXT_ |
| 94 | 1909 | Miss Bending Postcard [en] postcards No companion or independent key was found in a complete search of the available collection. The isolated strings remain source-limited. | SOURCE_ |
| 95 | 1908 | Florence Miller Pine Bush Postcard [en] postcards Most of the surviving lower text is readable as travel plans and a promise to write. Damage and several ambiguous signs prevent a complete reading. | SOURCE_ |
| 97 | Doc and Louise Morton Correspondence [en] postcards The clear passages repeat already known affectionate text from the correspondence. Only a few damaged marks remain uncertain. | PRIOR_ | |
| 99 | 1903 | E. G. Postcard of 1903 [fr] postcards The number line has a complete French reading. One token remains a minor transcription dispute because the source is unclear. | PLAINTEXT_ |
| 100 | 1906 | Market Drayton Postcard [en] postcards Two independent readers found ordinary English handwriting. Several pale words remain matters of transcription rather than cryptanalysis. | PLAINTEXT_ |
| 101 | 1921 | Paris to Sussex Postcard [en] postcards The card contains ordinary prose about an invitation, a holiday, and affection. Only a few pale words remain uncertain. | PLAINTEXT_ |
| 102 | 1911 | Jack and M. Jallett Postcard [en] postcards The full note is readable as a thank-you message ending with love from Jack. | NEW_ |
| 103 | 1904 | Nan's Dorchester Postcard [en] postcards The complete personal message is recovered, including an affectionate closing and an afternoon reminder. | NEW_ |
| 104 | 1909 | Kathleen and James Beckitt-Beecroft Postcard [en] postcards The complete message has been reconciled with the official transcript. The transformation is consistent throughout. | PLAINTEXT_ |
| 105 | 1908 | Harry and T. Abram Postcard [en] postcards The card is fully readable, including its affectionate closing from Harry. | PLAINTEXT_ |
| 106 | 1907 | Jack and Les Queen's Park Postcard [en] postcards The published reading is confirmed. The line asks whether the recipient has ever been in a similar situation. | PRIOR_ |
| 107 | Isabella and Sis Postcard [en] postcards A scholarly article already publishes the reading and explains the writing. The physical card's present accession remains unresolved. | PRIOR_ | |
| 108 | Burton and M. S. Pound Postcard [und] postcards No recoverable trace of the concealed text survives in the available image. A physical examination or better witness would be required. | DEAD_ | |
| 109 | 1911 | Harvey and Mabel Strong Postcard [en] postcards Nearly the entire affectionate message is readable. The final short group remains uncertain because several source marks are ambiguous. | SOURCE_ |
| 110 | 1908 | E. S. and Floyd Shoup Correspondence [en] postcards The romantic message was solved and published before this catalogue review. No additional related card was found. | PRIOR_ |
| 111 | 1918 | Forest Beefe Postcard [en] postcards The complete farewell is recovered, correcting an earlier public misreading of its opening words. | NEW_ |
| 112 | 1909 | Carrie and W. Briggs Postcard [en] postcards A complete public solution and plaintext already exist. The card is retained as a documented control. | PRIOR_ |
| 113 | 1911 | Nellie and Lillie Waters Postcard [en] postcards A specialist identified the writing as period shorthand and supplied an interpretation. It is not an unresolved cryptogram. | TRIAGED_ |
| 115 | Bristol and Langhorne Family Correspondence [en] postcards All three plaintexts have been publicly available since 2018. The group is retained as prior-solution evidence. | PRIOR_ | |
| 116 | Fritz and Leni Correspondence [de] postcards Both German plaintexts were published before this review. The recipient is identified in the records as Helene Obermeyer. | PRIOR_ | |
| 117 | 1914 | Spiez and Paula Lange Postcard [de] postcards A complete transcription was already published before the unsolved framing. No separate cipher problem remains. | PRIOR_ |
| 118 | 1911 | Myrtie and Leon Wilson Postcard [en] postcards The official collection record already publishes the complete plaintext. | PRIOR_ |
| 119 | Ralph Duckworth and Minnie Storey-Bates Correspondence [en] postcards Seven campaign messages are fully read, four are prior-solution controls, and one is limited by its source. A separate rebus item is cataloged independently. | NEW_ | |
| 121 | 1915 | Archie Corley Postcard [en] postcards The complete text is ordinary English ending with the signature A Friend. No substitution system is involved. | PLAINTEXT_ |
| 123 | Hale and Freeman Correspondence [und] postcards Sara Day identified the historical key and published the relationship behind the correspondence. This is a documented prior solution. | PRIOR_ | |
| 124 | 1906 | Charlie and Miss B. Correspondence [en] postcards Both affectionate messages are recovered. Two small source anomalies are marked as uncertain rather than forced. | NEW_ |
| 125 | 1913 | Ezra and Leeah Doane Correspondence [en] postcards A shared number alphabet opens all three cards, revealing plans, worries about privacy, and a missed visit with an apology. | NEW_ |
| 126 | 1910 | Harry and Miss Robbins Correspondence [und] postcards A specialist identified period shorthand and stabilized nearly every source row, but no defensible full plaintext is available. | SOURCE_ |
| 127 | Ray Bartley Postcard Packet [en] postcards All five private passages are fully transcribed and read. The remaining limits concern damaged source details, not the messages. | NEW_ | |
| 128 | Miss Wooster Correspondence [und] postcards A corrected record confirms repeated patterns and links among the cards, but no identifiable writing system or plaintext has been established. | SOURCE_ | |
| 129 | Fritz Lehmann Correspondence [de] postcards Nine targets are fully read, two are bounded by physical damage, and one retains five unreadable longhand lines despite a readable number block and signature. | NEW_ | |
| 131 | 1911 | M. H. Manton Correspondence [und] postcards The physical set, chronology, and traffic are documented, but no secure plaintext or sender identity has been established. Specialist review is still needed. | SOURCE_ |
| 132 | 1907 | G. Groves Correspondence [en] postcards Every group is read. The notes concern meeting plans, a safe arrival, kindness, and an assurance of honest affection. | NEW_ |
| 133 | W. Abbott Correspondence [und] postcards The corpus, chronology, routes, and inventory are complete, but the messages still require specialist shorthand readers. | SOURCE_ | |
| 134 | Fritz Salmen and Frl. Braun Postcards [de] postcards The public number alphabet is verified across the group. Three cards are fully read, seven are substantial partials, and 21 yield bounded phrases. | NEW_ | |
| 136 | Madeleine Boucheron Postcard [fr] postcards The number line reads as an affectionate souvenir. The closing is probably a challenge to guess the sender, but the final signature is uncertain. | NEW_ | |
| 138 | O. Davy and Nell Correspondence [en] postcards Both messages are completely read. They are affectionate notes signed George and include plans for Sunday contact. | NEW_ | |
| 141 | Annie Kepler Postcard [en] postcards The insert is fully read as an affectionate declaration signed with initials. | NEW_ | |
| 142 | Thompson and Edwin H. Mallison Postcard [en] postcards The complete playful and flirtatious message is recovered. | NEW_ | |
| 143 | E. R. Mobsby Postcards [en] postcards A shared key gives complete readings of both cards. | NEW_ | |
| 144 | Daphne Lidell Postcard [en] postcards All 26 tokens are decoded, completing the private portion of the note. | NEW_ | |
| 145 | Frederica Clark Postcard [en] postcards The message is fully read through its surviving text. Its unfinished tail reflects the original card rather than an unresolved key. | NEW_ | |
| 146 | Aimee L. Farrar Postcards [en] postcards The central rebus solution was published in 2021. The wider campaign corrects the names and accounts for four related context cards. | PRIOR_ | |
| 147 | Miss Dean Postcards [und] postcards The cards are linked to a 62-item shorthand set, probably by the W. Abbott writer. No reliable plaintext is yet available. | SOURCE_ | |
| 149 | Sallie and Peggy Lewis Postcard [en] postcards The full message is read as a note about Cardiff and is signed Mollie. | NEW_ | |
| 150 | 1912 | Lowell Postcard of 1912 [und] postcards Tests of several plausible systems do not yield a unique reading. The signs remain underdetermined. | SOURCE_ |
| 152 | Florence Maud Golding Postcards [und] postcards The two cards share a writer, system, and repeated initials, but no reversible mechanism or plaintext is known. Better source access is needed. | SOURCE_ | |
| 153 | Edna Mist Postcards [en] postcards Both cards are fully read. The messages discuss a mother's illness and Christmas. | NEW_ | |
| 154 | Edith Elsworth Postcard [en] postcards The complete reading is a list of terms and buildings. | NEW_ | |
| 155 | Walt and Miss Nicholls Postcard [en] postcards The complete text is read with a direct letter-number alphabet, confirmed by a previously solved card from the same correspondence. | NEW_ | |
| 156 | Abie and Henry Wulf Postcard [en] postcards One reversed alphabet accounts for all 80 tokens. Repeated words for affection and Henry's name provide internal checks. | NEW_ | |
| 157 | Flossie and Jack Stalland Postcard [en] postcards A direct letter-number reading accounts for every cell and yields a complete affectionate note signed Flossie. | NEW_ | |
| 159 | 1908 | Grace Hudson Postcard [und] postcards The source supports 71 to 73 marks, with 48 read securely. No tested reading rule predicted the remaining text. | SOURCE_ |
| 160 | Miss Adah Thompson Postcard [en] postcards A paired-alphabet Pigpen key accounts for all 58 cells. The complete reading preserves source anomalies and one uncertain modifier. | NEW_ | |
| 161 | 1903 | Miss Ramsay Postcard [en] postcards Direct Morse accounts for all 52 groups. Fifty-one are standard groups, while one exact unsplit run is not. | NEW_ |
| 162 | 1905 | W. T. Gale and J. E. Smith Postcard [und] postcards The source closes at 129 cells. Tests of several plausible systems produced no plaintext or key. | SOURCE_ |
| 163 | Grace Janson Valentine [en] postcards A direct letter-number reading accounts for all 84 legible values and recovers a complete playful note from Elsie. | NEW_ | |
| 164 | 1917 | Fannie J. Roberts Postcard [und] postcards The image supports a wide range of possible sign counts. A carefully limited test found no dependable key, plaintext, or writing system. | SOURCE_ |
| 165 | Bertha Linn Valentine Postcards [und] postcards The cards use the same system, but two independent transfer tests could not predict a complete withheld passage. No plaintext or key is established. | SOURCE_ | |
| 166 | 1903 | Miss Saines Postcard [und] postcards The transcription is stable at 24 clusters and 83 cells. No tested system or substitution key predicted a complete withheld row. | SOURCE_ |
| 167 | 1907 | K. Williams-Jones Postcard [en] postcards An adjacent-pair letter-number key accounts for every readable value and predicts both withheld rows. The letter anticipates a reunion and ends with love and kisses. | NEW_ |
| 168 | G. L. Serry Postcard [und] postcards The transcription is stable at 100 cells in 24 shape classes. Signs found only in the withheld sample prevent a complete reading, so no plaintext or key is established. | SOURCE_ | |
| 169 | Miss A. Underwood Postcard [und] postcards The signs follow a consistent visual grammar, but every natural mapping tested failed both withheld rows. No plaintext or key is established. | SOURCE_ | |
| 170 | Mrs. A. L. Jones Postcards [und] postcards All three cards and their rows are verified, but the only photograph cannot settle the exact units on the first two. No reading test ran, and the third card remained sealed. | SOURCE_ | |
| 171 | Miss Stirling Postcard [en] postcards A paired Pigpen reading represents all 95 positions and predicts three withheld rows. Ninety-three values are secure, while two small letter choices remain bounded. | MECHANISM_ | |
| 172 | Mr. Geo Bhedger Postcard [und] postcards The source is stable, but every form appears only once. Substitution and shape-based tests failed, leaving no plaintext, key, or dependable system. | SOURCE_ | |
| 173 | 1913 | Miss Unsworth Postcard [und] postcards A key that perfectly reproduces a public comparison card does not predict this target. No plaintext or key is established for the target. | SOURCE_ |
| 174 | Miss E. R. Perry Postcard [en] postcards One paired Pigpen key accounts for all 119 secure forms and predicts two withheld rows. Two forms remain uncertain because of the source. | MECHANISM_ | |
| 175 | Miss Marshall Postcard [und] postcards The source remains bounded at 214 to 235 visible forms. None of 42 fixed geometric readings predicted a complete withheld row, so no plaintext or key is established. | SOURCE_ | |
| 176 | Carl Wieler Postcard [und] postcards The source supports 336 visible candidates, but the overlay leaves the exact sequence unsettled. No reading test ran. | SOURCE_ | |
| 177 | Miss E. Barnard Postcard [und] postcards The source is stable across 13 rows. None of 4,752 registered tests produced a candidate or predicted a complete withheld row. | SOURCE_ | |
| 178 | Danny Reed Postcard [und] postcards The source supports 135 to 138 forms. Extensive registered tests produced no candidate or complete withheld prediction. | SOURCE_ | |
| 179 | Mrs. M. R. Robinson Postcard [und] postcards The readings disagree on both line breaks and count, leaving only a range of 189 to 227 elements. No agreed source model exists, so no reading test ran. | SOURCE_ | |
| 180 | Delia Fischer Postcard [und] postcards The source is stable across 19 rows. A large registered screen and an independent control produced no complete withheld prediction. | SOURCE_ | |
| 181 | Minnie Congleton Postcards [und] postcards The marks are visually compatible, but neither source count is settled. No reading test ran, and no plaintext, key, or dependable system is established. | SOURCE_ | |
| 182 | Miss Nelly Monnony Postcard [und] postcards The ten tracks are secure, but independent readers could not agree on one complete ordered sequence. No reading test ran. | SOURCE_ | |
| 183 | Pappie and Mabel Gregory Postcard [und] postcards The source is stable across seven rows. None of 74,304 registered screens produced an eligible reading. | SOURCE_ | |
| 184 | Mrs. A. Watkins Postcard [und] postcards The source is stable across eight rows. Hundreds of candidates survived initial tests, but none predicted a complete withheld row. | SOURCE_ | |
| 185 | Mr. C. Powell Postcard [und] postcards The rows are secure, but the count remains bounded at 125 to 129 forms in 22 to 27 groups. No reading test ran. | SOURCE_ | |
| 186 | Miss Emma Alwin Postcard [und] postcards The rows, group envelopes, and separators are secure, but the total remains bounded at 115 to 126 forms. No reading test ran. | SOURCE_ | |
| 187 | Miss Elsie G. Williams Postcard [und] postcards The rows are secure, but independent readers disagree on the groups, forms, and separators. No agreed source model was available for a reading test. | SOURCE_ | |
| 188 | Mrs. M. C. Hutton Postcard [und] postcards The rows and curved band are secure, but their internal units and separators remain uncertain. No reading test ran. | SOURCE_ | |
| 189 | Velma Chapin Postcards [und] postcards The first card has 12 secure rows and the second has three, but key boundaries on both remain unsettled. No reading test ran. | SOURCE_ | |
| 190 | J. E. Fortune Postcard [und] postcards The traversals are secure, but independent readers disagree on the groups, cells, ticks, and total units. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 191 | Anna Lackum Postcard [und] postcards Only two of 13 literal fields agree between readers, and none of the main windows matches exactly. The source conflict stopped work before any reading test. | SOURCE_ | |
| 192 | Miss Olive Ritter Postcard [und] postcards The broad rows are secure, but readers disagree on cells and strokes, and the later rows do not align. No reading test ran. | SOURCE_ | |
| 193 | R. B. Morrison Postcard [und] postcards Both readers agree on the rows but not on occurrences, groups, or separator roles. The destination also remains disputed, so no reading test ran. | SOURCE_ | |
| 194 | Breen Postcard [und] postcards One reader finds nine rows and 92 forms; the other finds ten rows and 115. With no agreed complete sequence, no reading test ran. | SOURCE_ | |
| 195 | Mr. J. Briggs Postcard [und] postcards The rows are secure, but readers disagree on group joins and gaps. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 196 | Miss Elvira Jungleseth Postcard [und] postcards The readers divide the card into ten bands with 112 forms or eight bands with 30 coarse groups. No exact row or group correspondence survives, so no reading test ran. | SOURCE_ | |
| 197 | Mr. A. Matthews Postcard [und] postcards The readers disagree on rows, units, and group membership. The source could not be settled, so no reading test ran. | SOURCE_ | |
| 198 | Reamer H. Hillan Postcard [und] postcards The source is stable and includes three withheld rows. None of 10,304 registered results passed both prediction and consistency tests. | SOURCE_ | |
| 199 | Miss J. B. Postcard [und] postcards The rows and groups are secure, but readers count 89 versus 95 signs and disagree on separators. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 200 | Alma Wolfram Postcard [und] postcards The readers align 130 forms but retain several conflicts and incompatible picture-side samples. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 201 | Estella White Postcard [und] postcards The rows and the absence of picture-side writing are secure, but readers divide the marks differently. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 202 | C. E. Knauff Postcard [und] postcards The readers disagree sharply on rows, cells, groups, separators, and overlays. No agreed source sequence exists, so no reading test ran. | SOURCE_ | |
| 203 | L. Brooks Postcard [und] postcards The readers align 87 forms, but 16 form clusters and every group and separator cluster remain disputed. No common withheld sample survived, so no reading test ran. | SOURCE_ | |
| 204 | George L. Sutherland Postcard [und] postcards The readers agree on the rows but disagree sharply on the form and group counts. Two rows also contain printed overlap that cannot be bounded, so no reading test ran. | SOURCE_ | |
| 205 | G. C. F. Ramsdew Postcard [und] postcards The readers agree on the picture-side rows but disagree on the number and structure of the address-side marks. Validation stopped before any reading test. | SOURCE_ | |
| 206 | Frank Srady Postcard [und] postcards The readers agree that no target appears on the picture side but disagree on the address-side rows. The source comparison stopped before any reading test. | SOURCE_ | |
| 207 | Lily G. Swale Postcard [und] postcards Both readers find 17 rows, but every row differs in its bounds or completeness. The source never reached an agreed form, so no reading test ran. | SOURCE_ | |
| 208 | Scott Postcard [und] postcards Both readers find 11 rows, but all row boxes differ and the recipient and locality remain disputed. No reading test ran. | SOURCE_ | |
| 209 | F. Hainge Postcard [und] postcards The readers agree on the rows but divide the watermark-crossed forms in incompatible ways. The source packet failed validation, so no reading test ran. | SOURCE_ | |
| 210 | Denis Gore Postcard [und] postcards The reader packets passed their seals but disagreed on the row count and contained invalid links. Validation failed before reconciliation, so no reading test ran. | SOURCE_ | |
| 213 | H. Riggs Postcard [und] postcards The row counts and even the presence of picture-side writing conflict. Reconciliation failed, so no agreed source sequence or reading followed. | SOURCE_ | |
| 214 | Unidentified Postcard [und] postcards The readers disagree on row geometry despite equal separator totals. Reconciliation failed, so no agreed source sequence or reading followed. | SOURCE_ | |
| 215 | Oakbank Postcard [und] postcards The readers disagree on forms, groups, separators, and geometry. Reconciliation failed, so no agreed source sequence or reading followed. | SOURCE_ | |
| 216 | Ben Hunter Postcard [und] postcards The headline counts agree, but the separators, groups, overlays, and withheld samples do not. Reconciliation failed, so no reading followed. | SOURCE_ | |
| 217 | Miss Smith Postcard [und] postcards One reader sees 13 horizontal runs after rotation; the other sees four vertical runs without it. Orientation reconciliation failed, so no reading followed. | SOURCE_ |