Longitude rewards facts for kids
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The longitude rewards were a series of huge cash prizes offered by the British government in the 1700s. The goal was to find a simple and reliable way for sailors to figure out their ship's longitude (its east-west position) while at sea. The prizes were created by a law called the Longitude Act 1714 and were managed by a group of experts known as the Board of Longitude.
Britain wasn't the first country to offer a prize for this. Spain had offered a reward as early as 1567, and the Netherlands also offered one. However, the British prize was the most famous, and it inspired many people to try and solve this difficult problem.
Contents
The Longitude Problem: Why Was It So Hard?
As ships began to sail across vast oceans, knowing their exact location became a matter of life and death.
Figuring out latitude (a ship's north-south position) was fairly simple. Sailors could measure the height of the sun at noon. But finding longitude was much harder. Early sailors used a method called dead reckoning. They would guess their position based on their ship's speed, direction, and the time they had been traveling. This was very inaccurate on long trips and often led to disasters.
Finding an accurate way to measure longitude was crucial for safe travel and for making correct maps. On land, it was possible to find longitude by observing the moons of Jupiter, but this was impossible on the rocking deck of a ship. The main challenge was finding a method that worked at sea.
Scientists and inventors explored three main types of solutions:
- Creating very detailed maps.
- Using the moon and stars for navigation (celestial methods).
- Building special clocks that could keep accurate time on a ship (mechanical methods).
The British government offered the Longitude Prize mainly for economic and political reasons. Controlling the seas meant more trade and power.
Creating the Prizes
In the early 1700s, several sea disasters highlighted the need for better navigation. In 1707, a British naval fleet crashed on the Isles of Scilly, and many sailors lost their lives because they didn't know their correct longitude.
This tragedy and other events pushed the British Parliament to act. In 1714, they passed the Longitude Act, which created the prizes. The prizes were offered for different levels of accuracy:
- £10,000 (worth millions today) for a method that could find longitude within one degree.
- £15,000 for a method accurate to within 40 minutes.
- £20,000 (a massive fortune, equal to over £3.5 million in 2025) for a method accurate to within 30 minutes.
The Board of Longitude was set up to judge the ideas. They could also give smaller amounts of money to help people with promising inventions. To win, an inventor's method had to be tested on a long sea voyage from Britain to the West Indies, which took about six weeks.
Who Won the Prize Money?
The Board of Longitude awarded money to many different people for their contributions. No one ever received the full £20,000 prize in one go, but some inventors received large sums over time for their amazing work.
Famous Winners
- John Harrison: He received the most money, a total of £23,065 over many years. He invented a series of amazing sea clocks, called marine chronometers.
- Thomas Mudge: He was awarded £3,000 for his own design of a marine timekeeper.
- Tobias Mayer: His widow was given £3,000 for his tables of lunar distances. These charts helped sailors use the moon to find their longitude. The famous explorer James Cook used Mayer's tables on his voyages.
- Thomas Earnshaw: He received £3,000 for improving the design of chronometers, making them easier to produce.
- Larcum Kendall: He was paid £800 to make a copy of Harrison's famous H4 watch, proving that the design could be recreated. His copy, K1, was also used by Captain Cook.
Many other inventors and scientists received smaller awards for their work on telescopes, sextants, and star charts.
John Harrison's Amazing Clocks
The most famous story from the Longitude Prize is that of John Harrison, a carpenter and clockmaker from a small village. When the Longitude Act was passed, he was just 21 years old. He dedicated his life to building a clock that could keep perfect time at sea.
Why was a clock so important? To find longitude, a sailor needs to know the exact time at their home port (like London) and the local time on the ship. The difference between these two times reveals their longitude. The problem was that pendulum clocks didn't work on a moving ship. Harrison had to invent a whole new kind of timekeeper that wasn't affected by a ship's rolling and pitching or by changes in temperature.
Harrison's Fight for the Prize
Harrison built a series of clocks, known as H1, H2, and H3. Each one was a brilliant piece of engineering. But his final masterpiece was the H4, which looked more like a large pocket watch.
In 1761, the H4 was tested on a voyage to Jamaica. It performed incredibly well, losing only 5.1 seconds in 81 days. This was far more accurate than the prize required. However, the Board of Longitude was hesitant to give him the full prize. They were mostly astronomers who favored the lunar distance method.
They gave Harrison part of the money but demanded that he share his secrets and prove that his watch could be copied by others. Harrison felt this was unfair. After years of struggling with the Board, he appealed directly to King George III. The King was impressed with Harrison's work and said, "By God, Harrison, I will see you righted!"
Finally, in 1773, Parliament awarded Harrison an additional £8,750. In total, he received £23,065 over his lifetime, a huge amount of money that recognized his incredible achievement. His work changed navigation forever.
See Also
- History of longitude
- Nevil Maskelyne
- Lunar distance (navigation)
- James Cook
- Longitude Prize
