Historical Navigation and Timekeeping

The 1707 British Naval Disaster

A major disaster for the British Navy occurred in 1707.
A fleet returning from the Mediterranean was caught in bad weather.
Navigated by dead reckoning due to lack of accurate noon sights.
Misjudged location led to ships being wrecked on the Scilly Isles.
- Resulted in the loss of four ships and over 1500 men, including the admiral.
Led to the British government offering a prize for a reliable method to measure longitude at sea.

John Harrison, a clockmaker, created a solution to measure longitude using time.
Traditional pendulum clocks were ineffective at sea due to motion and environmental factors.
Harrison's innovation: A clock that could work on a rocking ship.
- Hinged pendulum in the middle to counteract ship movement.
- Designed to withstand corrosion and temperature changes.
Successfully tested his clock, known as a chronometer, despite initial governmental resistance.

Chronometer: Accurate timekeeping device set to Greenwich time for determining longitude.
Sextant: Instrument to measure the angle of the sun at noon to find latitude.
Calculating longitude:
- Difference between local noon and Greenwich time indicates longitude.
- Example: Local noon vs. Greenwich 3 p.m. = 45 degrees west longitude.

GPS technology has replaced the need for sextants and chronometers.
Understanding traditional methods helps grasp the concepts of latitude and longitude.

Traveling around the world affects timekeeping:
- Westward travel results in a day delay upon return.
- Eastward travel results in a day gain.
Identified by Magellan's expedition in the 1500s.
- Despite accurate logging, they returned a day off from the local time.

Traditional navigation methods laid the groundwork for understanding global positioning and time zones.
The historical development of these methods underscores the importance of technological innovations in exploration and navigation.