2. Astrolabe: This instrument was used to measure the altitude of celestial bodies, such as the sun and stars. This allowed sailors to determine their latitude, or position north or south of the equator.
3. Quadrant: This instrument was similar to the astrolabe, but it was simpler to use. It was used to measure the altitude of celestial bodies and could also be used to determine latitude.
4. Cross-staff: This instrument was used to measure the angle between two objects, such as the sun and the horizon. This allowed sailors to determine their latitude.
5. Sand glass: This instrument was used to measure time. It consists of two glass bulbs connected by a narrow neck. Sand would flow from one bulb to the other, and the amount of time it took for all the sand to flow through was known.
6. Lead line: This instrument was used to measure the depth of water. It consists of a rope with a lead weight attached to one end. The rope would be lowered into the water, and the depth could be determined by measuring the length of rope that was out.
7. Chart: This is a map of a body of water, such as an ocean or a sea. It shows the location of land masses, islands, and other features, such as reefs and shoals.