He began diving in the ocean off San Diego in the 1930s before scuba tanks, face masks, and swim fins and at a time when lobsters, abalone, and sea bass were bountiful along Southern California shores. As a pioneer of modern free diving and a prolific innovator of spearfishing gear, Wally Potts preferred to use only his own lung power to dive deep under the sea. Potts, who set world records for spearing and landing large game fish, designed mechanisms that are key parts of the modern spear gun, died Feb. 5 in La Jolla of complications from diabetes. He was 83. "He was a true pioneer," said Eric Hanauer, who interviewed Potts for his 1994 book "Diving Pioneers" and included Potts in an exhibit he created on early divers, now on display at the Scripps Institution of Oceanography in La Jolla.

A Legacy of Innovation

His diving equipment consisted of a pair of strong lungs, a tolerance for cold temperatures, and vision so acute he earned the nickname "radar eyes." Fins were just an accessory. In an era before wet suits and fancy apparatus, Wally Potts was among the fathers of free diving. With a crude mask and an improvised fishing spear, he became the first member of the pioneering San Diego Bottom Scratchers to land a fish of more than 100 pounds: a 110-pound gulf grouper in September 1945. Later, applying his mastery as a metal worker with fellow Bottom Scratcher Jack Prodanovich, Mr. Potts designed spearfishing gear that helped revolutionize the industry.

Revolutionizing Spearfishing

"The Potts reel and his two-part trigger mechanism are still defining standards of modern spearfishing equipment," said Jim Cahill, a San Diego diving enthusiast and longtime friend. Mr. Potts, a legend among watermen for his diving prowess and design ingenuity, died Tuesday in La Jolla of complications from diabetes. He was 83. "On a fifty-fifty basis, Wally and I worked on everything in spearfishing gear that's on the market," said Jack Prodanovich, who welcomed Mr. Potts into the Bottom Scratchers in 1939.

Hollywood and Legacy

The designs, created in Mr. Potts' garage, included a plastic reel that allowed divers to subdue large fish underwater. Mr. Potts and Prodanovich had their own fling with Hollywood in 1977, with the release of the James Bond movie "The Spy Who Loved Me." They designed an underwater rocket for a scene in the film. "We had 30 days to do it and it had to shoot at least 30 feet," Prodanovich recalled. "We made it big enough to shoot 50 feet." To divers such as Cahill, a former lifeguard, Mr. Potts was the Babe Ruth of watermen. "There really was a tribe, and he was the tribal chief," Cahill said.