Navigational instrument

Navigational instruments refers to the instruments used by nautical navigators and pilots as tools of their trade. The purpose of navigation is to ascertain the present position and to determine the speed, direction etc. to arrive at the port or point of destination. Navigational instruments refers to the instruments used by nautical navigators and pilots as tools of their trade. The purpose of navigation is to ascertain the present position and to determine the speed, direction etc. to arrive at the port or point of destination. These instruments are used primarily to measure the elevation or altitude of a celestial object: