Ancient Tools of Navigation
In the old world people had as little as the sun and stars to help them navigate through the oceans. As time went by they created new ways on measuring depth and navigation.
Examples such as the Lead Line that helped them measure their depth and take a sample of the ocean by simply placing it in the water and letting it sink. An Astrolabe helped navigators measure angular heights of Polaris, it was considered useful onshore instead of the sea because it needed to be leveled with the horizon. Other tools that were used included a Quadrant and a Back Staff that helped greatly with the navigation at sea.
Examples such as the Lead Line that helped them measure their depth and take a sample of the ocean by simply placing it in the water and letting it sink. An Astrolabe helped navigators measure angular heights of Polaris, it was considered useful onshore instead of the sea because it needed to be leveled with the horizon. Other tools that were used included a Quadrant and a Back Staff that helped greatly with the navigation at sea.