Free levelled English reading practice. Read for meaning first, then use the full Speed Reading tool to time yourself and track your progress.
Navigation becomes difficult when familiar landmarks disappear beyond the horizon. The magnetic compass helped solve this problem by providing a directional reference based on Earth's magnetic field. Early knowledge of magnetism developed in China, where lodestone and magnetised needles were used in various contexts before compasses became established navigational tools. By the medieval period, magnetic compasses were also being used by sailors in the Mediterranean and elsewhere, although historians continue to investigate the routes by which knowledge and techniques spread. A compass needle does not point exactly toward the geographic North Pole; it aligns with the local magnetic field, and the difference between magnetic and true north varies by place and over time. Navigators therefore learned to account for magnetic variation. Combined with charts, astronomical observations and later instruments, the compass made open-water navigation more dependable. Its significance lies not in making navigation effortless, but in providing a portable reference when weather, darkness or distance removed other clues.
Comprehension questions
What physical field does a compass use?
Where did early knowledge of magnetic navigation develop?
Why does a compass not point exactly to geographic north?
