If you don't already, it's time to get to know English inventor John Harrison.
To mark April 3, John Harrison's 325th birthday, Google is celebrating the man behind the first marine chronometer to calculate longitude at sea. To honor him, Google shows the inventor hard at work with his clock-making tools in Tuesday's Doodle.
Born in 1693, Harrison lived in a revolutionary time for sea navigation. In 1707, tragedy hit England when 1,550 sailors lost their lives in a naval disaster off the Isles of Scilly, Cornwall. The disaster was said to have been caused by an error in navigation, and the British government came up with the longitude prize, which would award £20,000 for a method of determining longitude at sea.
Harrison, a self-educated clockmaker and carpenter, spent five years creating a "sea clock" that could accurately tell the time at sea, crucial to navigation over long sea voyages. He completed it in 1735 and spent a further two decades further developing the design. He completed a fourth design in 1761.
Harrison died at 82 years old.