Taximeter (nautical)

In nautical terms the taximeter is an instrument used to measure markings (marking: horizontal angle measured from True North in the N-E-S-O direction to a notable object) and other horizontal angles. It consists of a pin or alidade or visor or telescope that rotates on a vertical axis and a horizontal azimuthal circle graduated in degrees and whose origin is aligned with the line of cradle. It is similar in use and application to an aZimutal circle. For the origin of measurements to always be aligned with the ship's cradle the instrument must necessarily be attached to the ship's structure. This is why it is not usually used in small boats where the compass is usually used to replace the meter in some of its functions since the compass of markings is smaller and manageable.

By taking delays and using geometric techniques on the navigation chart you can determine the position, course, speed, etc. of a ship which is useful for piloting and navigation.

Two simple examples of its use: Collision course, constant delay.

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