WHEN he looked in the mirror, having done his 50 morning press-ups, John Piña Craven did not see James Bond. More often he saw an outsider who had scrapped and scraped his way into the navy, rather than gliding into it through Annapolis as the Cravens had always done. He liked to see glints of his mother’s Moorish-pirate ancestry, that hint of “black blood” that had bothered his Presbyterian father. The only time he approached Bond was during poker games, when he might smoke a cigar, and where few could beat him for calculated reading of an opponent.

To outside observers, however, his world came straight from Ian Fleming. Dr Craven’s job for many years was to spy on the Soviets using submarines. His mission, initially as chief scientist at the navy’s Special Projects Office, was to devise ways of finding on the deep ocean bed anything the enemy might have dropped or mislaid, including atom bombs. Equally he had to find ways of salvaging, before the Soviets did, anything America had lost there—such as, in 1968, the submarine Scorpion, and in 1966 a hydrogen bomb knocked out of a B52 during mid-air refuelling.

The depths of the sea were the last frontier of the cold war. It was not until 1960 that a Polaris missile was successfully test-fired from a submerged submarine, and not until 1965 that Dr Craven converted a nuclear submarine, the Halibut, into a secret spy ship full of cables, strobe lights, giant crab-claws and remote-controlled cameras. He was no submariner himself, having done his wartime service on the battleship USS New Mexico, and no sailor subsequently, just a civilian engineer and naval civil servant devoted to the sea. But the Halibut was a triumph. Thanks to Dr Craven’s improved thrust/vector control, it could hover invisibly and silently for hours over any tantalising object.

Fixing where to look was his special skill. As a mathematician he used Bayesian search theory, crunching multiple probabilities to produce contour maps and then to pinpoint a site to within a few hundred yards. Thanks to that, too, Halibut not only detected sunken craft and weapons but, in 1971, tapped into a submarine telecoms cable in Russia’s Sea of Okhotsk, opening up a universe of intelligence.

Dr Craven was also asked to push men further. Hence his work on the Trieste series of bathyscaphes, built to withstand the pressure 20,000 feet down, and the SeaLab project, training unprotected divers to descend to the ocean floor itself. In effect he, a non-diver influenced mostly by Jules Verne, was charged with turning human beings into “marine mammals”. SeaLab failed, and was abandoned. But he often reflected that what he was attempting, in the inky depths, was every bit as hazardous as trying to land men on the Moon.

Swallowing submarines whole

The best story of all concerned what the Soviets mislaid. In 1968 a submarine, K129, disappeared in the Pacific. Dr Craven was ordered to find it, mostly because it might be rogue and about to attack the United States. Halibut detected it, three miles down and wrecked by an explosion, and took 22,000 photos; the CIA then went wild, and in 1974 sent a specially built ship, the Glomar Explorer, to try to raise the submarine. On the pretext of mining manganese nodules, a giant claw would scrape it up; then the underbelly of the ship would open, swallowing the submarine whole.

The mission mostly failed, but the saga became a book and a film. Dr Craven was fingered as privy to the whole business. He knew something; but what bothered him most was that the cover story was untrue. Manganese could not feasibly be mined from the ocean floor. Moreover that lie, which he could not expose, had inspired other countries to waste money trying. He felt much less like Bond than Coleridge’s Ancient Mariner, with the albatross of state secrecy hung about his neck.

In many ways, the silent service—as submarines were called, even before they spied—was not ideal for him. He was noisy by nature, singing everything from Mozart to Pete Seeger, playing the piano, telling jokes. His mind was restless, curious and omnivorous. Tiptoeing through the shoals of naval etiquette, when much of his work did not officially exist, came hard to him. Eventually there were interviews, and a book, “The Silent War”, in which he trod very carefully, while bursting to tell all.

Nor was he done with the deep ocean. As a good liberal, he fell out of sympathy with cold-war bluster after a time, and turned to thinking how the ocean depths might usefully be shared. In 1970 his secret work had taken him to Hawaii. There in 1974 he set up a laboratory to use the temperature difference between deep cold water, and warm surface water, to produce electricity. He also began a project to grow crops cheaply by using condensation from cold deep-ocean water pumped through pipes to the shore. With good results on both counts, he began to think the ocean might be used to power whole cities, starting in the Marianas. Old age slowed him, but he kept that at bay by swimming, snorkelling and applying cold-as-the-ocean water-packs as he slept. When he looked in the mirror, he was still not 007. But he was not far from those marine mammals he had once tried to create, who might pluck from the bottom of the ocean things that were well worth knowing.