Send a comment on this item to LII: Send a comment on this item to LII staff, who on weekdays will usually reply within 24 hours. Lost at Sea: The Search for Longitude This site is a companion to a Public Broadcasting Service (PBS) NOVA program that tells the story of how British clockmaker John Harrison solved the problem of calculating longitude and thus "discovered the key to navigating on the open seas." The site provides a program transcript, information about secrets of ancient navigation and the current Global Positioning System (GPS), and thoughts from scientists about recent scientific challenges. Also includes a teacher's guide. http://www.pbs.org/wgbh/nova/longitude/ Asterisk * indicates required field. Your Name Your Email Address * We will not sell or provide your email address to anyone else. Comment * Enter the verification code as it is shown in the box below. This helps prevent automated submissions. *