…Christopher Columbus’ crews are getting worried. If you’ve ever traveled to a new place, you know how they were feeling—”Are we there yet? How much longer?” Remember: those guys were probably okay with the idea that the Earth is round, but they didn’t know it for sure. After a couple of months, maybe they’re starting to think traveling west to reach the east isn’t such a hot idea after all.
Sailors in those days didn’t have an accurate way of knowing how far east or west they were. A compass can tell you which direction you’re traveling. An astrolabe will tell you how far north or south you are and what time it is. Casting a log will give you a rough idea of how far you’ve traveled. There was simply no way for Columbus and his crew to know exactly how far west they were.
Back to the beginning of The Western Civ User’s Guide to Time & Space