Page:A Voyage to Terra Australis Volume 2.djvu/532

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The medium error for eight points deviation of the Investigator's head on either side of the magnetic meridian, was therefore very nearly one-twentieth part of the dip; and (,0498 called) ,05, the decimal expression of it, is the common multiplier to the dip for obtaining the radius of error at any situation in the southern hemisphere; as the (,0531 called) ,053 from the first table, is the common multiplier from England to the magnetic equator. Had the observations in both hemispheres been equally numerous, the multipliers might perhaps have been exactly the same; but it is also