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197)
Longitude would exceed 4° 17'; and in the second case, it would exceed 3° 3'. All the other horary Motions are limited between these. And the Error resulting from any other horary Motion of the  Moon, at the Time of the Observation, may be in like manner determined.
4. But taking FD for instance of 2' 12", I find, in the Triangle CPO, the Angle CPO, or the Arc DO to be of 12' 31", 9: And that the Angle CP[[underlined]] O [[/underlined]] would be of 8' 31", 2. Now let the Line C[[underlined]] Oz [[/underlined]] cut the Limb in [[underlined]] z [[/underlined]]: And as soon as the Stars comes to [[underlined]] 0 [[/underlined]] it will emerge in [[underlined]] z [[/underlined]]. The Difference 0 [[underlined]] 0 [[/underlined]] is of 4' 0", 7. And so the little Arc 0[[underlined]] 0 [[/underlined]] expressed in Parts of a great Circle amounts to 3' 34", 9, for the Argument of the Error in Longitude. 
For the Astronomical Calculation gives the Emersion when the Star is in or very near the Point O: But in reality, the Emersion happens when the Star is in the Point [[underlined]] O [[/underlined]]. And therefore if the Moon's horary Motion was of 28', the Error in Longitude, or the Time spent in describing the Arc [[underlined]] 0 [[/underlined]]O, would be of 7 min. 40 4/9 sec. which amount to an Error of 1° 48' 2/8 of Longitude. And the horary Motion of 38' would produce an Error in Longitude of 5 min. 39 1/4 sec. in Time, or of 1° 17' 3/5. And in like manner we may find the [[underlined]] Error [[/underlined]] in Longitude [[underlined]] resulting [[/underlined]] from any other given horary Motion of the Moon.
 5. Likewise making CD equal to CD, I find, in the Triangle CPo, the Angle CPo or the