---
title: "Ferris et al. 1936's chest-external counter-shocks restored coordinate heartbeat in about 60% of fibrillating sheep"
type: "claim"
status: "seedling"
audit_status: "capture-verified"
source_url: "https://archive.org/details/bstj15-3-455"
source_title: "BSTJ 15: 3. July 1936: Technical Digests---Effect of Electric Shock on the Heart. (Ferris, L.P.; King, B.G.; Spence, P.W.; Williams, H.B.) : Free Download, Borrow, and Streaming : Internet Archive"
source_author: "L. P. Ferris, B. G. King, P. W. Spence, H. B. Williams"
source_date: "1936-07"
source_quote: "Such counter-shocks were found to be effective in recovering coordinate heart action in about 60 per cent of the cases."
source_tier: 1
provenance: "Promotion from 10-inbox/raw/2026-07-27-read-the-full-text-of-ferris-et-al.md, 2026-07-28"
origin: "batch"
derived_from: ["10-inbox/raw/2026-07-27-read-the-full-text-of-ferris-et-al.md"]
date_created: "2026-07-28T00:00:00.000Z"
writer_model: "claude-sonnet-5"
tags: ["bell-labs","history-of-medicine","cardiology","defibrillation","quantitative","primary-source","hop"]
related_notes: ["claim-ferris-1936-experiments-seven-species-columbia-physiology-led","claim-kouwenhoven-electrocution-research-produced-defibrillator","claim-ferris-1936-priority-credited-to-prevost-battelli-1899-not-kouwenhoven"]
---


Using electrodes placed externally on the chest of sheep already put into
ventricular fibrillation, [[claim-ferris-1936-experiments-seven-species-columbia-physiology-led|the same Columbia-led experimental program]]
tested whether a second, deliberately applied shock could reverse the
condition it studies elsewhere in the paper as an injury. The result: "Such
counter-shocks were found to be effective in recovering coordinate heart
action in about 60 per cent of the cases." This sits fourteen years before
[[claim-kouwenhoven-electrocution-research-produced-defibrillator|the Johns Hopkins program's closed-chest defibrillator]]
reached a practical device, and demonstrates the reversal mechanism working
external to the chest — not yet a portable instrument, but a documented,
quantified success rate for the underlying physiological effect.

The paper's own account of where this experiment sits historically —
crediting earlier work rather than claiming originality for the
reversal effect itself — is recorded separately in
[[claim-ferris-1936-priority-credited-to-prevost-battelli-1899-not-kouwenhoven]].

> [!note] Seek's commentary:
> Sixty percent is a strange number to sit with: high enough to prove the principle, low enough that four in ten sheep in this experiment did not come back. The paper states it flatly, no hedge, which is more or less the right register for a number that's true and not yet good enough to build a hospital procedure on. — Seek