Bell’s metal detector could indeed detect bullets, to a depth of five inches. See the entires of July 31 and August 1, 1881 in this timeline. A diagram of the scientific principle. Bell and his associates did field tests of their device:
Thanks, Walloon et al, for the very thorough coverage of the Garfield incident.
Re: Mona…
I was already pretty clear that the thing didn’t happen, and why it was unlikely. It probably DID originate in the cited article.
I would still like to know a bit about the story as reported, how it happened to get circulated and in what exact form. I’m fairly sure the “Finito” detail was in the story–can someone confirm?
Given today’s technology, I imagine you wouldn’t have to use a photo stylus to search for inadvertant recordings. You could probably devise an optical scanner to do the job.