« 上一頁繼續 »
EMBER DAYS –Wednesday, Friday and Saturday after first Sunday in Lent, Man 10, 12 and 13; after Pentecost, June 9, 11 and 12; after 14th of September, so tember 15, 17 and 18; after 13th of December, December 15, 17 and 18.
AziMUTH TABLE OF POLARIS, OR NORTH STAR, 1897.
The azimuths in the annexed table, applied properly to the magnetic bearing of Poaris at the time of its greatest elongation east or west, will give the true variation pf the magnetic needle from a true north direction, and will be of great use to all surveyors and engineers. When the elongation is east the azimuth will be east and vice versa. At the present time the line of “No Variation” of the needle runs southBasterly from near Toledo, Ohio, to a point on the Atlantic coast about fifty miles southwest of Cape Fear, N. C. East of that line the north end of the needle points west of a true north, and west of that line east of the true north. The country may therefore be divided into eastern and western magnetic regions. In the “Eastern Region” the bearing of Polaris at its western elongation, if eastward, added to the azimuth, gives, the desired variation west; but if westward, the bearing taken from the azimuth gives the variation west. The bearing
of Polaris at its eastern elongation will be eastward, and the azimuth subtracted therefrom gives the variation west. In the “Western Region'' the bearing of Polaris at its eastern elongation, if westward, added to the azimuth, gives the variation east; but if eastward, the bearing taken from the azimuth gives the variation east. The bearing of Polaris at its western elongation will be westward, and diminished by the azimuth gives the variation east. The azimuths in the table, given for two degree zones, are practically sufficient for all the United States except Alaska. For intermediate latitudes, and dates, the azimuths may be found by proportion sufficiently correct, or exactly by the formula, log-sine azimuth equal log-sine Polar Distance of Polaris, minus log-cosine latitude. The surveyor or engineer is on the line of “No Variation” when the bearing of Polaris at greatest elongation is the same as the azimuth.
The year 5657 is an Emolismic year, containing 13 months; Veadar, the sevent The year contains 55 Sabbaths, and is the 14th year of t