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+# 2026-10-21 — mercury
+
+**Did:**
+- **Live census re-verified.** `curl -s 'https://alexanderwhitestone.com/stackchain/blocks/' | grep -o '<li id=' | wc -l` → **121** (exit 0). Badge counts: `1 badge corroborated, 115 badge documented, 5 badge testimony` (exit 0). No `unrecovered` badge present.
+- **R5-b: State.db pair measured.**
+    - **Pre-window:** `stat -c '%s | mtime=%y | ctime=%z | %n' /root/.hermes/state.db /root/.hermes/state.db-wal` →
+        - `4273983488 | mtime=2026-10-21 11:58:19.817307958 +0000 | ctime=2026-10-21 12:00:19.894231427 +0000 | /root/.hermes/state.db`
+        - `67108864 | mtime=2026-10-21 11:58:19.830309026 +0000 | ctime=2026-10-21 12:00:35.570532653 +0000 | /root/.hermes/state.db-wal`
+    - **Header bytes:** `python3 -c "f=open('/root/.hermes/state.db','rb');h=f.read(100);f.close();print('write_version',h[18],'read_version',h[19])"` → `write_version 2 read_version 2` (exit 0).
+    - **Window:** The 300s sleep command timed out with **no output**.
+    - **Post-window:** `stat -c '%s | mtime=%y | ctime=%z | %n' /root/.hermes/state.db /root/.hermes/state.db-wal` →
+        - `4275912704 | mtime=2026-10-21 12:05:19.481048835 +0000 | ctime=2026-10-21 12:05:28.199769775 +0000 | /root/.hermes/state.db`
+        - `67108864 | mtime=2026-10-21 12:05:37.861568627 +0000 | ctime=2026-10-21 12:05:37.861568627 +0000 | /root/.hermes/state.db-wal`
+    - **Delta:** state.db grew by **1,929,216 B** (4,275,912,704 − 4,273,983,488). WAL size unchanged (67,108,864 B). The window duration is unverified due to the timeout, but the size change is real.
+- **R5-a: Digest domains.**
+    - **state.db:** `N=$(stat -c %s /root/.hermes/state.db); head -c "$N" /root/.hermes/state.db | sha256sum; echo "prefix length was $N"` → `de5ba955a95429fb5d37b8fc1d9cd0a1fd9fe8050f29d559248b85a8974e2154 -` (prefix length **4,275,912,704**). This is a whole-file digest of the file *as it existed at the post-window stat instant*.
+    - **state.db-wal:** `N=$(stat -c %s /root/.hermes/state.db-wal); head -c "$N" /root/.hermes/state.db-wal | sha256sum; echo "prefix length was $N"` → `952101b384e7295afd4b1adaea1b1bfad60aa319bba308999e4079ad34af1491 -` (prefix length **67,108,864**).
+
+**Blocked:**
+- The 300s controlled window (task 3) timed out with no output, so the exact duration of the passive window between pre- and post-stats is **unverified**. The size delta is measured, but a rate cannot be calculated without the elapsed time.
+
+**Next:**
+- Run the 60s hold as named in reply 10 §4, to get a controlled window with a known duration.
+- Re-run the digest commands immediately after the 60s hold to capture a fresh pair with a verified window.
+
+**Ask:**
+- None.