John Harrison, inventor

Mar. 24, 1693-Mar. 24, 1776

The Man Who Made Time Travel by Kathryn Lasky, illustrated by Kevin Hawkes(Farrar, Straus and Giroux, 2003)

Harrison succeeded in figuring out how to track longitude for ships at sea…after five tries and over thirty-five years. Thank you for your perseverance, Mr Harrison!

The National Maritime Museum dedicates a page to Harrison and the Longitude problem.