The fist explorers had no compasses to help them find their way. Instead, they learned how to use the position of the stars in the night sky to guide them. The Sun's position helped them in the daytime.
[In the 15th century CE, sailors used a cross-staff to get a rough idea of where they were. They pointed it at a star so that the sliding cross piece touched the horizon on the bottom and the star on the top. A scale on the bar was used with a book of tables to work out the sailors' position.]
[Early explorers worked out how fast they were travelling by timing how long it took a floating object to travel their ship's length.]
*[The compass was invented in China - Chinese sailors were using it to help them find their way more than 1,000 years ago.]
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