Brilliant_ The Evolution of Artificial Light - Jane Brox [19]
Eighteenth-century whalers suffered their own particular perils, but the seas were dangerous for all sailors. Most navigation tools were rudimentary and the charts imprecise. Once night fell or weather closed in the coast, mariners had few lights to help them steer clear of sandbars, stone reefs, or the debris of old wrecks. What lights there were—often no more than open coal or wood fires on the headlands and burning baskets of pitch or oakum atop long poles—were of limited help, for they barely penetrated the fog and the dark and didn't always stand up to the prevailing winds and storms that battered them. The work of keeping the light alive could be unceasing: on a windy night, an open fire could consume a ton of coal or countless logs. The endless demand for fuel for coastal fires was one of the primary reasons for the deforestation of the island of Anholt off the coast of Denmark.
The smoke-clouded lanterns of the few lighthouses were no better. Their flames—sometimes open to the elements, at best enclosed in glass or horn and magnified with reflectors or convex lenses—were small and unsteady. The lamps, often possessing multiple wicks, had to be constantly snuffed, guarded, fanned, and fed. They were hard to light in the cold, and the keepers—ill supplied, isolated, and miserably paid, themselves barely protected from the wind and rain—might need to place hot coals near the lanterns to prevent the oil from congealing. Despite the best efforts of the keepers, along the British coast alone—the best-lit coast in the world in the early eighteenth century—more than five hundred ships foundered every year.
At times it was lights themselves that sunk ships, for well-intentioned beacons could be deceiving. Almost all of them in the eighteenth century were fixed—there was no system of flashing lights to help distinguish one lighthouse from another as there would be in later times—and although a fixed light could help orient those who knew the waters, it was of little help to someone unsure of his bearings. A ship approaching land after a long, wind-tossed voyage could be far enough off course that the navigator might mistake the light he encountered for a different one farther along the coast. Or a light, being precarious, would go out, and the navigator might find no light where he expected one to be. It was also true that a terrestrial light might appear to be celestial. Pliny the Elder, speaking of seamarks in Roman times, wrote, "The only danger is, that when these fires are thus kept burning without intermission, they may be mistaken for stars, the flames having very much that appearance at a distance."
Lights could also be intentionally deceiving: wreckers intent on stealing washed-up cargo sometimes set a lantern on a dark headland hoping it would be taken for a true seamark, though their usual method, wrote lighthouse historian D. Alan Stevenson, "was to drive an ass bearing 2 lanterns along the shore, to represent a vessel in motion and so lure a ship to destruction among the near rocks and shoals." Wreckers weren't the occasional wayward souls. Historian Bella Bathurst notes, "Many coastal villages staked their livelihoods on the exotic plunder to be found in dead and dying ships; the wreckers