reduction to center—¹ The amount which must be applied to a direction observed at an eccentric station, or to an eccentric signal, so as to reduce such direction to what it would be if there were no such eccentricity. ² [ASTRONOMY] One of the values used in finding the equation of time.  See also station, eccentric. 

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Source: NSPS “Definitions of Surveying and Related Terms“, used with permission.

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