elgar’s clock faceHis 1920s notebook draws the alphabet as polar coordinates: radius 1–3 (the number of arcs) and angle in π/4 steps (eight orientations). 24 cells, 24 letters — which is why two letters of the alphabet get no symbol at all.
Grid editor
the same key, laid flatThe snowflake: each arm is an orientation, each ring an arc count. Type a letter into any cell. Original fill is the layout from my original snowflake.html (no J, no Q). Turn rotates the whole key one arm — note letters never change ring, which is exactly why rotation alone can never alter an arc count.
Message
what to encipherLetters not present in the key are dropped and listed. Line layout controls how the output splits into manuscript rows — 29 / 31 / 27 matches Dorabella itself, which matters if you use the per-line key schedule.
Key motion
what makes it a cipherA key that never moves is an ordinary substitution. A key that moves between symbols is a real cipher, and everything here is a symmetry of the polar key: rotate, reflect, permute the rings — applied on a schedule.
Encipher applies the motion (+k·step); decipher undoes it (−k·step). Same key, same schedule, opposite sign. Verify round-trip proves the two directions are exact inverses for your current settings.
Glyph convention
how the glyphs are drawnWhich feature of an arc carries its direction name — the apex, the opening, or a quarter-turn from either. The manuscript does not say, so it is a setting. Every convention is a global relabelling: it changes the picture and the names you would write down, never the cryptanalysis. The legend shows all 24 as drawn.
Ciphertext out
the resultThe glyphs as they would appear on the page, with the plaintext letter under each, plus the same thing in arcs+direction notation. Send to ciphertext hands it to the Decipher page along with your key and settings.