Way back when, a safecracker was called a "yegg" or a "yeggman". Not a word you run into very often. Early 20th century. Seems to have first shown up in print in a New York Evening Post article in 1903 or 1904. Supposedly coined from a hobo named John Yeager.
Also short for "Crazy Motherfucker".
What they would do, see, because explosives were actually pretty easy to come by, is line the hinges of the safe with putty, forming a channel into which they would pour a measure of nitroglycerin. Then, after this precise, and delicate step was completed they would, and here's the important part, hit the safe with a sledgehammer.
Oddly enough, that's not the crazy part.
Yeggs would traditionally keep their nitro with them at all times. The idea was that they would inject it into a rubber ball which they hung from their necks. And then advertise to the world that this is what they did. It stopped a lot of fights. Either before they happened or right after the first punch was thrown. People learned fast that you didn't get into a fight with a yegg.
So, how does all this fascinating education on hundred year old criminal behavior apply to today?
Seems two gentlemen held up a grocery store and, when confronted by the safe that no one had the combination to, gave up. Now if they'd had a yegg and some nitro with them, the news would be a lot more fun to read about.