The sextant was invented over 300 years ago. Although mostly used by sailors, many early explorers also relied upon this tool. This device uses a telescope and mirrors to measure the angle between the horizon and a star or the sun. From this angle the user can determine their distance from the equator (latitude).

   To figure out your exact position, , you need to know your exact longitude. This can be done easily with any accurate clock.
   Then the sextant is used to determine the latitude. The position of the sun or a star will not change. Only the measured angles will change as your position changes.

   To begin using your sextant, look at the horizon through the small telecope and the horizon mirror. The horizon mirror is is a round glass screen that is half silvered to work as a mirror. The image of the star or sun is reflected onto horizon mirror by the index mirror. The index mirror has to be movable for this to work. You will see the sun and the

horizon side by side as seen in the round image.
   The index mirror is attached to the movable arm. The bottom of the arm slides along a curved, graduated scale. Once the two images are aligned you simply read the scale to determine the angle of your latitude. So , do you know where you are?