John Harrison (watchmaker)

John Harrison was an 18th-century English clockmaker renowned for solving the problem of accurately measuring longitude at sea. He designed innovative marine chronometers—highly precise timekeeping devices—that remained reliable despite the ship's movements and changing conditions. Prior to his work, sailors struggled with navigation errors, leading to dangerous voyages. Harrison’s advancements allowed sailors to determine their east-west position with remarkable accuracy, greatly improving maritime safety and exploration. His contributions are considered a major milestone in horology and navigation, earning him recognition beyond his era.