This experience alerted the navy to the problem of breathing normal air during a deep sea dive, and it started experimenting with a helium-oxygen mix. A US naval diver preparing for a dive in 1955.

Fact Check. A vintage photograph perennially shared on social media purports to show an actual deep-sea diving suit from 1925 that looks more like a mash-up of the Tin Man from "The Wizard of Oz ...