Experiment 184
F4.1. 0092 tested grid paths on rectangles of chosen widths with K4 starting at a corner. On the copper, K4 does not start at a corner: it occupies the last four 31-character lines of the lower-left plate, its first row holding only OBKR at columns 28-31 after K3's last letters and the ?. The plates' lines are ragged (29-33 characters; transcript in knowledge/01-facts.md). Routes are built on three physical grids: K4's own four lines, the lower plate's 14 lines, and the left side's 28 lines; for each, rows or columns from each corner, straight or back and forth, diagonals both ways, and spirals both ways; K4's letters are taken in the order a route visits K4's cells. Each route and its inverse, then (A) or before (B) a repeating key 1-26 on 8 table classes (F6's compiled tester); K4 against 15 shuffled copies.
What the method does with the 24 known letters.
On the copper, K4the carved letters The 97 letters cut into the copper at the CIA, shown at the top of every experiment page. starts near the end of a line, right after K3the earlier messages The three solved parts of the sculpture. and a question mark, and runs on for three full lines. If Sanborn wrote his message into that physical shape along some path, down the columns, back and forth, round in a spiral, the carved order would follow from it. We try every such path on the real layout, with a repeating secret wordthe secret word The word or string a cipher needs besides the method. before or after, and compare with scrambled copies.
Words in the margin are defined on the glossary page.
The carved letters go in at the top; the reading comes out at the bottom.
On the copper K4 begins near the end of a line, after K3 and a question mark, then fills three lines of 31. A message written into that real shape along some path would be carved in a different order.
Every path along rows, columns, diagonals and spirals, from each corner, straight or back and forth, over K4's lines, the lower plate and the whole left side; each undone, then a repeating key of 1-26 on the sculpture's tables, before or after; 15 scrambled copies.
The shortest key that fits K4 is 23 after the path and 26 before, as on the copies (22 and 26), and K4 leads them nowhere. F4.1 closed for paths over the layout.
This experiment produced no candidate: the search ruled everything out before a full text was built. Its product is the bounded negative in section 7.
Redo the method on a few letters with pencil and paper.
The same steps run by the code on the real letters.
K4's cells read down the columns from the top left: UTVOWTXTTOQMGSZHJFUQPLSKBSWSEGOKDLZKIZZFWXBATBTJWJCFKDLLIRUGVDKQIUQAHPWURIANNUGFEOKBKBSNCKSYAROPR
Family, key space, the constraint under test, and the clues it reads.
C3 (Sanborn's sculptural, visual habits), C1 ('matrix codes'), F4 ('Sanborn's visual systems'); the 31-letter lines as a grid (knowledge/04-structure.md). Model: message written along a route over the plate's cells, carved row by row (or the reverse), with a periodic tableau key before or after. Statistic: 0134's fixed statistic (cells (order, period) where K4 is live in more routes than every copy, against each copy's count against the rest), and the shortest live period.
Written before the run; the result decides it.
No route gives K4 a live period below the copies'; the cells where K4 leads stay inside the copies' range. Zero candidates.
The harness's record: candidates, gates, loss, and the negative result this experiment leaves behind.
73 routes; shortest live K4 A 23 B 26 (copies 22, 26); K4 above every copy in 0 of 52 cells (copies 0-1)
What was searched, as the harness recorded it.
How this experiment sits among the others is on the lineage page; its family's open hypotheses are on the families page.