In coastal navigation it is used either to measure the angle between two objects spaced apart on the shoreline, when the sextant is held by the observer in a horizontal position, or the angle from the top of a high object to the water line, when it is held vertically.
Kunxweme lolwandle isetyenziswa mhlawumbi ukulinganisa imbombo phakathi kwezinto ezimbini ezinesithuba phakathi kwazo kumgca wonxweme xa isixhobo sohulinganisa ukuphakama kwelanga ukufumana ubuphi benqanawa sibanjwe ngumqwalaseli kwindlela ethe tyaba, okanye imbombo ukusuka entla kwento ephezulu ukuya kumgca wamanzi, xa ibanjwe ngokuthe nkqo.