Gimme Some o' That Technology!

I've been snuffling around at Wikipedia, trying to figure out the answer to a conundrum for my book. Not to quote it or anything (oooh, you naughty boy!) but just to understand the thing.

I've "known" as a matter of received knowledge that these old Victor 78s I've been listening to rather obsessively could be no longer than three minutes, because that's how much a 78 side could contain. But as I look at the timings of these things in digital format (because, pout pout, my editor won't buy me a Victrola and a stack of eyewateringly rare and expensive 78s, the catchpenny swine), many of them are quite a bit longer than that. In particular, "Darlin' Cora," recorded by B. F. Shelton with Ralph Peer in 1927, is 3:50 long, according to iTunes.

At any rate. My problem to solve. But reading a Wiki article on the history of recording technology, I came across this paragraph, which elicited a hearty guffaw. Also, I laughed.

In the 1930s radio pioneer Guglielmo Marconi developed a system of magnetic sound recording using steel tape. This was the same material used to make razor blades, and not surprisingly the fearsome Marconi-Stille recorders were considered so dangerous that technicians had to operate them from another room for safety. Because of the high recording speeds required, they used enormous reels about one metre in diameter, and the thin tape frequently broke, sending jagged lengths of razor steel flying around the studio.

Yes, I can see why it didn't catch on....

George Martin, on the talkback mic: I'm afraid we've a spot of trouble, lads.

John Lennon: What is it, Georgie?

Martin: Well, you see, we've had to call an ambulance for Geoff Emerick; I'm afraid there's a spot of blood on the tape op's chair. And on the ceiling, too, now that I look. Oh, dear, and splashed about the studio walls, too, rather higgledy-piggledy. It's going to take ever so long for EMI to have the cleaners in.

Paul McCartney: It's that bloody Marconi machine again, innit? That's the fourth tape op we've lost this week!

Martin: Yes, the razor-sharp, high-tension recording medium wrapped itself around his head and torso a right treat. Rather looked like a Chinaman undergoing the Death of a Thousand Cuts three months in. Well, bright spot: Geoff's screams of agony have died away somewhat. Don't know if that's because it's stopped being quite so dreadfully painful, or because he's weakened from loss of blood. Blessing for the rest of us, at any rate. Shall we run though that new one, then? What is it? "You Should Know Your Mother"?