When André Galerne was a boy, he loved to explore caves along the French coastline, descending to the shores of deep underground lakes. As he gazed into the dark, silent water, a lifelong fascination with diving was born. Galerne went on to found International Underwater Contractors, once among the world's largest deep-sea construction companies, and to invent diving technologies that transformed the industry. He died on May 6 at 81.

Galerne's early life has the shape of a boy's adventure story. Born in Paris in 1926, he joined the French Resistance at 16. After the liberation of Paris, Galerne earned an engineering degree, but the sea still beckoned. In 1951, he introduced himself to Jacques Cousteau; Galerne sailed for a year on the Calypso and learned scuba. "Cousteau was interested in filmmaking and exploring," says Lionel Galerne, who became CEO of IUC in 1996. "My father wanted to make a living out of it."

In 1952, Galerne and some former comrades in arms formed Sogetram, one of the first commercial diving firms. The company fixed bridges and performed other civil-engineering projects, but Galerne chafed under government regulation. He sold his interest and immigrated to Canada, where he formed IUC. In 1962, he moved the business to New York City. From there, IUC handled local construction projects -- for example, inspecting the bedrock on the site of the World Trade Center -- and launched into the global oil industry. IUC divers serviced drilling platforms from California to Angola.

As he aged, Galerne stopped diving, but he never stopped inventing. His most important innovation was a portable pressurized chamber. Concerned that injured divers could not be moved to hospitals until they spent hours or days in a decompression chamber, Galerne designed a chamber that could be lifted by helicopter -- in many cases, to the hyperbaric medical facility he helped establish in Aberdeen, Scotland. "When they got there, medics could go into the chamber and do whatever it took to save the diver's life," says Lionel Galerne. "Before that, he would have had to suffer through decompression and hope he got out in time to make it to a hospital."

Galerne saved other lives as well. One evening at a party in Manhattan, he met a fire chief who was distraught because one of his men had been hospitalized with carbon monoxide poisoning. Galerne had purchased two decompression chambers for training divers; he suggested that placing the firefighter in one of them might force out the carbon monoxide. "They brought him in on a gurney," says Lionel Galerne. "He was under pressure with pure oxygen for half an hour, and he walked out. For the next five years, we became the 911 emergency call center for carbon monoxide poisoning in New York City."

Brusque, brave, and brilliant, Galerne over the years became an icon to ambitious young divers, says Bill Crowley, who worked for IUC in the '70s and '80s. "Back then," says Crowley, "there were three places you went if you wanted to dive deep. The North Sea. The Gulf of Mexico. And IUC. IUC was André."