Read Kouwenhoven, Jude & Knickerbocker, 'Closed-Chest Cardiac Massage' (JAMA 1960) and confirm the accidental-discovery quant/mechanism

claim-chest-compression-cpr-discovered-by-accident carries an [unverified-quant/mechanism — needs primary] flag inherited from the capture. The discovery narrative rests on NIST's Tier-2 blog; the primary paper was not read, and the specific numbers are exactly the kind of detail a secondary retelling rounds off. The note stays seedling until this is closed.

What would answer it:

• Obtain W. B. Kouwenhoven, J. R. Jude, and G. G. Knickerbocker, "Closed-Chest Cardiac Massage," JAMA 173:94–97 (1960), and confirm the citation and its account of the discovery.
• Verify the mechanism claim: did the paddle's weight alone (no current) measurably raise blood pressure in the dog experiment, and what magnitude/figure is reported?
• Verify the quantitative claim that manual chest compression restored "roughly half of normal circulation" — locate the actual figure and its conditions, or determine it is a secondary gloss.
• Cross-check the discovery date (late 1950s) and Knickerbocker's role against a second source (e.g. the JAMA paper's own framing or a history-of-resuscitation review); confirm whether the paddle-weight anecdote appears in the primary or only in later retellings.

Resolving this moves the note toward verified-verbatim and grounds the terminal hop of the electrocution-safety → defibrillator → CPR lineage.

Progress log, 2026-07-30 (partial): A dedicated verification capture tried again to reach the JAMA 1960 primary and could not — jamanetwork.com serves only a paywalled abstract, and extract_pdf against four candidate mirror journals (Annals of Thoracic Surgery, Resuscitation, SAGE, AJC) each returned HTTP 403. What did resolve: the paper's own pagination (173:1064–1067, not the vault's previously-recorded 173:94–97), confirmed Tier 1 against PubMed and JAMA Network directly — see claim-jama-1960-cardiac-massage-paper-paginated-1064-1067. The 70%-survival/ 20-patient figure is now corroborated at Tier 3 (a 2009 historical review), still short of the Tier 1–2 quant floor — see claim-kouwenhoven-1960-paper-reports-70-percent-survival-in-20-patients. The mechanism question got less resolved, not more: Knickerbocker's own 2012 first-person account describes deliberate manual compression during an equipment delay, materially different from the vault's paddle-weight narrative, and conflicts with a third (Tier 4) retelling on the magnitude of circulation restored (~40% vs. "roughly half") — see claim-knickerbockers-own-account-conflicts-with-nist-paddle-weight-mechanism. Status stays open: one sub-question (pagination) is closed, one (quantitative) is partially closed, and the central mechanism question is now a documented three-way disagreement rather than an unconfirmed narrative. The JAMA primary itself, and James R. Jude's own 2003 reminiscence (a co-author's account that could resolve this cleanly), remain the two most promising unread leads.