As a boy, Stewart fell in love with the sea by fishing with his father on the pier at Scripps Institution of Oceanography in San Diego, Calif. “When he’d catch a fish, I would take a look at it and run up to the old Scripps aquarium and see what that fish was,” Stewart said years later. When Emile Gagnan and Jacques-Yves Cousteau perfected the “Aqualung” in 1943, which allowed diving with relatively cheap equipment, and without being tethered to a boat by an air hose, Stewart was fascinated. Since high school, he had spent many hours spear-fishing as a free diver off the Scripps pier, and was ready to stay in the water longer. Once he did that, he realized that scuba gear would be a boon to ocean researchers. He took the concept to Scripps, where he had been a volunteer since the early 1950s; in 1960, he was hired as the Institution’s diving officer. “Jim’s goal was not to make scientists out of macho divers,” says Scripps researcher Paul Dayton, “but to make safe divers of good scientists.” Stewart developed comprehensive training programs for Scripps oceanographers, and then personally trained thousands of divers in safe scuba techniques. The U.S. military took notice, and adapted his training program to help keep their own divers safe. He helped NASA develop their underwater training techniques for astronauts — NASA’s Neutral Buoyancy Facility is the closest astronauts can get to “weightless” for training on Earth’s surface.
“Among scientific and technical divers, Jim Stewart enjoys the status that Chuck Yeager has among professional pilots,” says dive historian Eric Hanauer. “Jim was a diver’s diver.” Stewart was a research diver himself, having studied marine botany at the University of Southern California and the University of Hawaii. He even explored new craters in the Pacific — formed days earlier by hydrogen bomb tests. He was also responsible for training and certifying all scientists from all over the world who did research diving in the Arctic and Antarctic oceans for the National Science Foundation. Stewart spent nearly 50 years at Scripps before he retired in 1991 — but still did the training and certification for the polar divers for NSF. He died June 7, at 89.