Explains the concepts of latitude and longitude, which are used to locate places on Earth. It describes how latitude is measured in degrees north or south of the equator and how longitude is measured ...

English clockmaker John Harrison revolutionized long distance seafaring in the 18th century, solving the problem of calculating longitude at sea and devising tools that helped sailors navigate with ...

Imaginary lines -- Sea before time -- Adrift in a clockwork universe -- Time in a bottle -- Powder of sympathy -- Prize -- Cogmaker's journal -- Grasshopper goes to sea -- Hands on Heaven's clock -- ...