A voyage towards the North pole undertaken by His Majesty's command, 1773 . ie fextant. This error will equally affeQ: all the obfervations taken near* the fame time, and therefore cannot be difcovered< from the comparifon of feveral obfervations. Under* the equator, an error of one minute in altitude, near* the prime vertical, will only produce an error of* four feconds in the apparent time; but in the latitude of 14. A P P E N D I X.** of eighty degrees it will caufe an error of twenty-three feconds. As we generally took feveral fucceflive ob-*< fervationsj any error in the obfervation
A voyage towards the North pole undertaken by His Majesty's command, 1773 . ie fextant. This error will equally affeQ: all the obfervations taken near* the fame time, and therefore cannot be difcovered< from the comparifon of feveral obfervations. Under* the equator, an error of one minute in altitude, near* the prime vertical, will only produce an error of* four feconds in the apparent time; but in the latitude of 14. A P P E N D I X.** of eighty degrees it will caufe an error of twenty-three feconds. As we generally took feveral fucceflive ob-*< fervationsj any error in the obfervation itfelf will be generally independent of the reft; and as I have calcu- lated each feparately, the conclufions will fhew which are erroneous, by their differing much from trhe mean of all, which cannot but be very near the truth. **In calculating thefe obfervatlons, I found by the logboard how much we had altered our latitude fmce the lafl; obfervation; and fometimes, when we had an obfervation the noon following the obfervation for the time, the latitude of the fhip at the time the altitudes were taken was inferred from it. As moft•* of our altitudes were, obferved when the fun was near** the prime vertical, a fmall error in the latitude wiH not produce any confiderable change in the time;indeed, if it is exaftly in the prime vertical, it will not make any change at all. ** To find the Longitude from thefe obfe
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