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pin falls on, in the horizontal line; as ſuppoſe, if the Sun is near the Horizon, you put the pin in 2, or 3, on account of the obliquity of the ſhadow; but, if the Sun hath greater altitude, then place it in 4: and ſuppoſe the ſhadow falls on 5, ſo have you a Rectangular Triangle, the Legs being formed by the Scales of equal parts, and the Sun's Rays is the Hypothenuſe; then work by this analogy,
| as the Log. of the length of the ſhadow, 5, ___ _ | 0,69897 |
| Is to the Log. of the Perpendicular, 4, _ | 0,60206 |
| So is Radius, ___ _ | 10,00000 |
| To the Tangent of the Sun's Alt. 38° 39' | 9,90309 |
and, note! if the ſhadow falls between the diviſions, then take the proportional part of the logarithms, and work as before, as if the ſhadow falls on 51⁄4 parts, then take a quarter of the difference of the next leſs, and greater Arcs, and add it to the logarithm of the leſſer Arc, and work with it as in the laſt Example; by which Rule you can never err a minute, either in the altitude or the time; and you may ſafely ſet the watch thereby. This Problem is univerſal, and is of the utmoſt utility to the practical Navigator, as well as for the exerciſe and amuſement of every private ſtudent, by land.
Problem 35. To regulate and adjuſt the motions of the Planets from noon, or midnight, as found in the Nautical Almanac, to any other intermediate hour and minute of the day or night required, and conſequently to find their true places in the Zodiac, in the Planisphere, and their ſituations, at all times, with reſpect to, and their progreſſive motion among the fixed
