In olden days, sailors used to find direction by suspending a piece of ___________.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Context**: In ancient times, sailors needed a reliable way to determine their direction while navigating the seas. They did not have modern instruments like compasses or GPS.

2. **Identifying the Tool Used**: Sailors found that certain materials could help them find direction. One such material is a magnet, which has distinct magnetic poles (north and south).

3. **How the Magnet Works**: When a magnet is suspended freely, it can rotate and align itself with the Earth's magnetic field. The north pole of the magnet will point towards the Earth's magnetic north, while the south pole will point towards the magnetic south.

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