À PROPOS DE CET ÉPISODE
The ability to determine a ship's position at sea was the deadliest problem of the 18th century, a challenge that turned the simple question of "Where am I?" into a matter of national security.
While sailors could easily find their latitude by measuring the height of the sun or the North Star, longitude remained a lethal mystery because it is inextricably bound to time.
Since the Earth rotates 15 degrees every hour, a navigator only needs to know the time at their home port compared to the time aboard ship to calculate their east-west position.
However, in the 1700s, this was impossible in practice; pendulum clocks relied on gravity and stable floors, making them useless on a ship that pitches, rolls, and experiences extreme changes in temperature and humidity.
The cost of this ignorance was measured in thousands of lives and a fortune in sunken ships.
The gravity of the crisis was punctuated by the 1707 Scilly naval disaster, where Admiral Sir Clowdisley Shovell’s fleet struck rocks due to navigation guesswork, claiming nearly 2,000 sailors.
While astronomers like Galileo and Newton looked to the "clockwork universe" of the stars and Jupiter’s moons for a solution, mechanical inventors struggled to build a "chronometer" that could withstand the rigors of the Atlantic.
The desperation of the era even led to bizarre proposals like the "Wounded Dog theory," involving a quack remedy called the Powder of Sympathy.
Ultimately, the British Parliament's Longitude Act of 1714 offered a king’s ransom of £20,000 to anyone who could solve the problem, sparking an intense global rivalry to bridge the gap between time and space.
