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[[top left]] 175) [[/top left]]

by the Star the 10th of [[underlined]]January[[/underlined]], If I add the Moon's periodic Revolution, corrected by the Moon's Apogee, the Node, and the Sun's Place (on which, by Sir [[underlined]]Isaac Newton[[/underlined]], it depends) I shall have the Moon there again some time in [[underlined]]February[[/underlined]], and if to that Time I add another period, I shall have her there again another Time in [[underlined]]March[[/underlined]], and so through the Year, which will give her Place 12 Times, and if 12 Observations are made, we shall have her place for 144 Times; and if 30, for 360 Times. A Table being thus made, which the Mariner carries to Sea, he may find the Place of the Node to 2 or 3 Seconds, tho' he knows not his Longitude within 4 Degrees; and as above he may find the Moon's Place, if it happens to be marked in the Table, he hath over-against it the Hour at the known Longitude; if only near it, then as the Moon's horary Motion is to the Difference, so is 13° 60' Minutes to a 4th Number, to be added or sub[[scribbled out]]s[[/scribbled out]]tracted from the Time in the Tables, according as I find her before or behind.

  Note, if he hath the Moon's Place within half a Degree in an Ephemeris, he may also have her Parallax and horary Motion within 2 or 3 Seconds, which will not cause an Error of 360 Seconds, or a Degree in the Longitude, which will come within the Limits set by Act of Parliament: And therefore I hope it will be found I have a Right to the Premium, there being no Instruments to be used to make it impracticable, but only a few Calculations by Trigonometry, which good Logarithms have made easy. Gent. Mag. 1738 p. 12.