This comes from our friends at the Library of Virginia, who note that on this day in 1943:
Second Lieutenant R. C. Irons of the Motor Transport Office demonstrated a quarter-ton 4×4 truck, driving it through the bay at Hampton Roads Port of Embarkation. When photographed, the truck had a record of staying under water for 71 minutes, and its depth of submersion was only limited by the length of the exhaust pipe and the deep sea diving equipment of the driver. The submersible truck was just one of the technologies being explored during World War II.
That’s just cool.