Compete to crack secrets lost to history—for fun, clout, and (no) profit

• STATUSACCEPTED
• BY@offgramercy
• WRITE-UP8 September 2026

Problems › 160 › solution › 1

A mechanically exact Pigpen reading that stays irregular

A diagonal field with two kinds of dot

The cipher occupies seven oblique rows, read left to right after rotating and straightening the message field without reflection. Two source readers independently agreed on 58 cell positions, arranged in 15 physical blocks. Detached round dots end blocks; dots close to a frame may modify it. The final long curve is outside the cadence and is not another character.[1]

A paired alphabet fits the later blocks too

The working system is paired-alphabet Pigpen. The frame gives an adjacent letter pair, and one internal dot selects its second member. The native orientation and source row order are retained. The conventional row-major alphabet, inverted dot assignments, orientation changes, and reversed traversals failed the recorded untouched controls. This is not a key accepted on the opening phrase alone.[2]

Applying the key to the recorded source classes

The published attack describes the convention as paired Pigpen. Its drawn alphabet and the source reader’s mnemonic names are different notations, however: a label such as CORNER_BL cannot safely be treated as the typeset corner that its name might suggest. The saved source-only descriptions do not provide a complete drawing-to-label crosswalk. This edition therefore uses the exact source classes in the key below. It aligns the already recorded occurrence readings; it does not reconstruct source shapes from the answer.[4]

“Not observed” means that modifier state has no secure occurrence on this card; no extra letter value is supplied for it here. Occurrence numbers count cells within each physical row. For example, R01.02 and R01.03 share U_FRAME_DOWN with different dot states; R03.04 and R03.01 similarly distinguish the two recorded C_FRAME values. The R07.03 cluster remains outside the ordinary single-dot column.

The source-only anomaly record independently confirms that U_FRAME_UP and U_FRAME_DOWN have opposite orientations, and that F_CORNER has a short inner branch. It does not independently identify an open side for the U forms or establish a typeset outline for every corner label. Those geometric details still require the source image; the named-class key makes the surviving transcript usable without pretending that its labels are drawings.

Seven rows, fifteen blocks

Complete source-faithful output

HOPE TO
SEE YOU
LUCK SOOH WITH
OUT FOJ THREE
COU HTRY
LOUE YOKELS
HO[P?]HOO

The letters are not a fluent reconstructed sentence. The source gives SOOH, FOJ, COU / HTRY, and LOUE. The fifth line even splits its apparent word across a detached physical stop. Those features remain in the edition.

A blind anomaly check rejected the easy repairs

The tempting changes were SOOH to “soon,” FOJ to “for,” COU HTRY to “country,” and LOUE to “love.” A sealed source-only reinspection found that the frozen shapes were correct and rejected those language-led changes. All secure cells continue to encode back under the one paired alphabet. The clean later blocks served as controls, keeping the reading from being adjusted merely to fit the first line.[2]

One source detail remains qualified. At R07.03 the O/P frame is secure, but four overlapping small marks do not establish a normal single-dot modifier. P is the strongest paired-key reading, so the diplomatic result is HO[P?]HOO. It is one cadence position with a doubtful modifier, not four new characters.

What is not claimed

All 58 cell positions are accounted for, but the writer’s intended fluent wording is not recovered. The final modifier bracket is not a resolved source fact. No sender or relationship is identified. MISS. HOPE. is a commercial portrait caption; it was not used as a crib, and it is not evidence that the sender or recipient was the photographed person.

The address corrects the portal’s Thompsson to Thompson. The cancel securely gives 13 July 1907, while locality and time remain qualified. HCP’s 29 August 2026 record was marked “Not solved” with no key or note. The local 1,875-record snapshot and bounded exact-item searches found no linked card or prior answer. The result is an exact mechanical edition new to those checked sources, not a universal first-ever claim or a polished intended message.[3]

References

• HCP1467 source record, Historical Ciphers Portal
• Complete source-faithful transcript and mechanical result, research corpus (legacy P151)
• Prior-reading search, provenance, and claim limits
• Frozen source-class transcript, 58-cell occurrence ledger, source-only shape and modifier audit, and recorded paired-key outputs; the crosswalk uses these existing records, not new drawings