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AZIMUTH TABLE OF POLARIS, 1894.

(Computed by S. Hart Wright, Ph. D., Penn Yan, N. Y.)

The azimuths in the annexed table, applied properly to the magnetic bearing of Polaris at the time of its greatest elongation east or west, will give the true variation of 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 southeasterly from near Toledo, Ohio, to a point on the Atlantic coast about 50 miles southwest of Cape Fear, N. C. East of that line the north en of the needle points west of a true north, and west of that line east of a 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 Cesired 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 subtractel 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, or dates, the azimuths may be found by proportion sufficiently correct, or exactly by the formula, log-sine azimuth-log-sine Polar distance of Polaris-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.

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Polaris. o tance of 65

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121 15 4

50

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January.

211 15 4

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February..

111 15 5

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February..

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March.

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March.

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March.

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December.. 311 14 441 25 271 27 11/1 29 71 31 141 33 35 1 36 10 1 39

THE SEASONS. 75TH MERIDIAN TIME. Winter begins, 1893, December 22, 8:53 a. m., and lasts 89 days, 1 hour, 6 minutes.

Spring begins, 1894, March 20, 9:59 a. m., and lasts 92 days, 20 hours, 5 minutes. Summer begins, 1894, June 21, 6:04 a. m., and lasts 93 days, 14 hours, 24 minutes. Autumn begins, 1894, September 22, 8:28 p. m., and lasts 89 days, 18 hours, 41 minutes.

Winter begins, 1894, December 21, 3:09 p. n. Trop'l year, 365 days, 6 hours, 16 minutes.

TO FIND THE TIME OF GREATEST ELONGATION OF POLARIS. By adding the numbers in the annexed table for any given latitude to the time of meridian passage of Polaris (the Pole Star), given in another table, the time of its great western elongation is found. If the same number be subtracted instead of added, we get the time of greatest eastern elongation. At the time of either

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elongation the magnetic Constant bearing may be taken with for the compass, using that Elonga- elongation which occurs at tion. night. The eastern elongations occur at night from H. M. S. April 1 to October 11, and 5:54:48 the western elongations oc5:54:44 cur at night all the rest of 5:54:39 the year. Correct local time 5:54:35 is to be used, and bearings 5:54:30 taken on the star promptly 5:54:25 on time; but an error of 5:54:20 half a minute or even a 5:54:10 minute in the timepiece 5:54:10 will not invalidate the 5:54:05 bearing, as Polaris then 5:54:00 Imoves nearly vertically.

EMBER DAYS.

First Sunday in Lent..
Pentecost..

September 14...
December 13..

.February 14, 16 and 17 ........May 16, 18 and 19 ..September 19, 21 and 22 .December 19, 21 and 22

CHRONOLOGICAL CYCLES.

G. (5) Roman Indiction...
(6) Julian Period...
(7) Dionysian Period..
(8) Jewish Lunar Cycle......

27

....6607

223

11

(1) Dominical or Sunday Letter... (2) Epact-(Moon's Age, Jan. 1).................... 23 (3) Lunar Cycle or Golden Number.... 14 (4) Solar Cycle... Explanatory Note.-The Dominical Letter indicates the day of the year on which the first Sunday occurs; G is the 7th letter, and the 7th of January will be Sunday. The Golden Number is the number in a cycle of 19 years, which shows how many years have passed since New Moon fell on January 1. This and (1) are chiefly used in fixing the Cate of Easter. No. (4) indicates the number of years that have elapsed since the current cycle of 28 years began. The first cycle began with the year 10 and is used to find (1.) Roman Indiction is a cycle of 15 years, and is of no utility except to chronologers. Julian Period is a cycle of 7980 years, and is the product of (3), (4) and (5), and when completed (3), (4) and (5) will coincide or begin at the same time. Dionysian Period is a cycle of 532 years, and is called the Great Paschal Cycle, being the product of the Solar and Lunar Cycles. This an (6) are chiefly used in chronology. The Jewish Lunar Cycle is always three less that (3); used only by the Jews in fixing the time of their festivals. HEBREW CALENDAR, 1894.

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MOHAMMEDAN CALENDAR, 1894.

Jan.
Feb.

7 Redjeb begins..

29

8 Sheban begins..

March 8

30

9 Ramadan begins...

7

30

10 Shawal begins..

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Mohammedan Months.

gorian
Date.

Jan.

81

30

Feb. 7 29
30
March 8
29
April 7
May
June 5

6

30

30

July 5

2 Saphar begins..

Aug. 4

Sept. 2
Oct.

30

2

Oct. 31 30

Nov. 30 29
Dec. 29 30

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April
May
June
July 5 29
Aug. 3 30
Sept. 2 29
Oct. 1 30
Oct. 31 29
Nov. 30 29
Dec. 29 29
Jan. 26 30

The year 5654 began September 11, 1893, or sunset of the 10th, and is embolismic, or a leap year, containing 13 months and 384 days, and is the eleventh of the 298th Jewish Cycle of nineteen years. The year 5655 begins October 1, or at sunset of September 30, 1894.

3 Rabia I. begins..

4 Rabia II. begins.
5 Jomhadi I. begins..
6 Jomhadi II. begins.
7 Rejeb begins....

Note.-The Mohammedan era began July 18, new style, or July 15, old style, on Thursday in the year 622 A. D. The year is lunar, containing 12 moons, and 354 or 355 days, and hence slides backward through the twelve Gregorian months in thirty-three years. The year 1311 began July 15, 1893, and ends July 4, 1894. The year 1312 begins July 5, 1894, and ends June 23, 1895.

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Apply to standard time by adding or subtracting the correction in minutes given in the table. If the first be correct, the resulting local time will be correct.

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SHOWING THE DAY OF THE WEEK OF ANY DATE, OLD STYLE OR NEW,

BEFORE OR AFTER CHRIST.

EXPLANATION.-Under or over each month will be found the names or abbreviations for the days of the week, arranged in seven different orders or sequences, reading from left to right. These are marked as sequence A, sequence B, and so on. At the right or left of each sequence is given the centurial

year of the century for which that sequence may be used-old style dates, or reckonings under the Julian Calendar, marked at the left; new style dates, according to the Gregorian Calendar, at the right; thus 16 at left of sequence D shows that this sequence is to be used for all old style dates from 1600 to 1699, as the Cate

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