In October 1928, doctors slid a dying eight-year-old polio patient into a massive airtight cylinder powered by vacuum cleaner motors, and within a minute she was breathing again. This episode traces the iron lung from that first clinical use through the polio terror of the 20th century, a story of garage inventions, bitter patent wars, and the human resilience of people who spent their entire lives inside these machines.

We explain the negative pressure mechanics that mimic the diaphragm, the patent fight where John Haven Emerson broke Harvard's monopoly using centuries-old prior art, and the plywood respirators that democratized the technology in Australia and Britain. We then examine the 1952 Copenhagen outbreak, where positive pressure ventilation slashed fatality rates and made the iron lung nearly extinct, and how COVID-19 revived inte ...