Дава Собел – Longitude (страница 3)

His every success, however, was parried by members of the scientific elite, who distrusted Harrison’s magic box. The commissioners charged with awarding the longitude prize—Nevil Maskelyne among them—changed the contest rules whenever they saw fit, so as to favor the chances of astronomers over the likes of Harrison and his fellow “mechanics.” But the utility and accuracy of Harrison’s approach triumphed in the end. His followers shepherded Harrison’s intricate, exquisite invention through the design modifications that enabled it to be mass produced and enjoy wide use.

An aged, exhausted Harrison, taken under the wing of King George III, ultimately claimed his rightful monetary reward in 1773—after forty struggling years of political intrigue, international warfare, academic backbiting, scientific revolution, and economic upheaval.

All these threads, and more, entwine in the lines of longitude. To unravel them now—to retrace their story in an age when a network of orbiting satellites can nail down a ship’s position within a few feet in just a moment or two—is to see the globe anew.

2. The Sea Before Time

They that go down to the Sea in Ships, that do business in great waters, these see the works of the Lord, and His wonders in the deep.

—PSALM 107

Dirty weather,” Admiral Sir Clowdisley Shovell called the fog that had dogged him twelve days at sea. Returning home victorious from Gibraltar after skirmishes with the French Mediterranean forces, Sir Clowdisley could not beat the heavy autumn overcast. Fearing the ships might founder on coastal rocks, the admiral summoned all his navigators to put their heads together.

The consensus opinion placed the English fleet safely west of Île d’Ouessant, an island outpost of the Brittany peninsula. But as the sailors continued north, they discovered to their horror that they had misgauged their longitude near the Scilly Isles. These tiny islands, about twenty miles from the southwest tip of England, point to Land’s End like a path of stepping-stones. And on that foggy night of October 22, 1707, the Scillies became unmarked tombstones for two thousand of Sir Clowdisley’s troops.

The flagship, the Association, struck first. She sank within minutes, drowning all hands. Before the rest of the vessels could react to the obvious danger, two more ships, the Eagle and the Romney, pricked themselves on the rocks and went down like stones. In all, four of the five warships were lost.

Only two men washed ashore alive. One of them was Sir Clowdisley himself, who may have watched the fifty-seven years of his life flash before his eyes as the waves carried him home. Certainly he had time to reflect on the events of the previous twenty-four hours, when he made what must have been the worst mistake in judgment of his naval career. He had been approached by a sailor, a member of the Association’s crew, who claimed to have kept his own reckoning of the fleet’s location during the whole cloudy passage. Such subversive navigation by an inferior was forbidden in the Royal Navy, as the unnamed seaman well knew. However, the danger appeared so enormous, by his calculations, that he risked his neck to make his concerns known to the officers. Admiral Shovell had the man hanged for mutiny on the spot.

No one was around to spit “I told you so!” into Sir Clowdisley’s face as he nearly drowned. But as soon as the admiral collapsed on dry sand, a local woman combing the beach purportedly found his body and fell in love with the emerald ring on his finger. Between her desire and his depletion, she handily murdered him for it. Three decades later, on her deathbed, this same woman confessed the crime to her clergyman, producing the ring as proof of her guilt and contrition.

The demise of Sir Clowdisley’s fleet capped a long saga of seafaring in the days before sailors could find their longitude. Page after page from this miserable history relates quintessential horror stories of death by scurvy and thirst, of ghosts in the rigging, and of landfalls in the form of shipwrecks, with hulls dashed on rocks and heaps of drowned corpses fouling the beaches. In literally hundreds of instances, a vessel’s ignorance of her longitude led swiftly to her destruction.

Launched on a mix of bravery and greed, the sea captains of the fifteenth, sixteenth, and seventeenth centuries relied on “dead reckoning” to gauge their distance east or west of home port. The captain would throw a log overboard and observe how quickly the ship receded from this temporary guidepost. He noted the crude speedometer reading in his ship’s logbook, along with the direction of travel, which he took from the stars or a compass, and the length of time on a particular course, counted with a sandglass or a pocket watch. Factoring in the effects of ocean currents, fickle winds, and errors in judgment, he then determined his longitude. He routinely missed his mark, of course—searching in vain for the island where he had hoped to find fresh water, or even the continent that was his destination. Too often, the technique of dead reckoning marked him for a dead man.

Long voyages waxed longer for lack of longitude, and the extra time at sea condemned sailors to the dread disease of scurvy. The oceangoing diet of the day, devoid of fresh fruits and vegetables, deprived them of vitamin C, and their bodies’ connective tissue deteriorated as a result. Their blood vessels leaked, making the men look bruised all over, even in the absence of any injury. When they were injured, their wounds failed to heal. Their legs swelled. They suffered the pain of spontaneous hemorrhaging into their muscles and joints. Their gums bled, too, as their teeth loosened. They gasped for breath, struggled against debilitating weakness, and when the blood vessels around their brains ruptured, they died.

Beyond this potential for human suffering, the global ignorance of longitude wreaked economic havoc on the grandest scale. It confined oceangoing vessels to a few narrow shipping lanes that promised safe passage. Forced to navigate by latitude alone, whaling ships, merchant ships, warships, and pirate ships all clustered along well-trafficked routes, where they fell prey to one another. In 1592, for example, a squadron of six English men-of-war coasted off the Azores, lying in ambush for Spanish traders heading back from the Caribbean. The Madre de Deus, an enormous Portuguese galleon returning from India, sailed into their web. Despite her thirty-two brass guns, the Madre de Deus lost the brief battle, and Portugal lost a princely cargo. Under the ship’s hatches lay chests of gold and silver coins, pearls, diamonds, amber, musk, tapestries, calico, and ebony. The spices had to be counted by the ton—more than four hundred tons of pepper, forty-five of cloves, thirty-five of cinnamon, and three each of mace and nutmeg. The Madre de Deus proved herself a prize worth half a million pounds sterling—or approximately half the net value of the entire English Exchequer at that date.

By the end of the seventeenth century, nearly three hundred ships a year sailed between the British Isles and the West Indies to ply the Jamaica trade. Since the sacrifice of a single one of these cargo vessels caused terrible losses, merchants yearned to avoid the inevitable. They wished to discover secret routes—and that meant discovering a means to determine longitude.

The pathetic state of navigation alarmed Samuel Pepys, who served for a time as an official of the Royal Navy. Commenting on his 1683 voyage to Tangiers, Pepys wrote: “It is most plain, from the confusion all these people are in, how to make good their reckonings, even each man’s with itself, and the nonsensical arguments they would make use of to do it, and disorder they are in about it, that it is by God’s Almighty Providence and great chance, and the wideness of the sea, that there are not a great many more misfortunes and ill chances in navigation than there are.”

That passage appeared prescient when the disastrous wreck on the Scillies scuttled four warships. The 1707 incident, so close to the shipping centers of England, catapulted the longitude question into the forefront of national affairs. The sudden loss of so many lives, so many ships, and so much honor all at once, on top of centuries of previous privation, underscored the folly of ocean navigation without a means for finding longitude. The souls of Sir Clowdisley’s lost sailors—another two thousand martyrs to the cause—precipitated the famed Longitude Act of 1714, in which Parliament promised a prize of £20,000 for a solution to the longitude problem.

In 1736, an unknown clockmaker named John Harrison carried a promising possibility on a trial voyage to Lisbon aboard H.M.S. Centurion. The ship’s officers saw firsthand how Harrison’s clock could improve their reckoning. Indeed, they thanked Harrison when his newfangled contraption showed them to be about sixty miles off course on the way home to London.