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17. Example: January 8, 1917. Find the times of high waters and low waters at Burntcoat Head, Nova Scotia.

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oh 26m a. M.

39 A. M. 52 P. M. 05 P. M.

EXPLANATION OF EXAMPLE 18.

On page 118 of the Nautical Almanac, January 17th, the moon's upper transit is more than 12 hours, and for that reason the upper transit for the 16th is used, 16d 18h 23m, from which subtract the correction 18m for longitude 9 hours east, which gives the moon's upper transit at Nagasaki, to which add the high water interval, 7h 54m, and the result will be the astronomical date and time of high water, 17d olh 59m, and being less than 12 hours is also civil time P.M.

To the moon's upper transit at Nagasaki, 16d 18h 05m, add the low water interval, 1h 4lm, which gives the astronomical date and time of low water, 16d 19h 46m. To this add 1 day and subtract 12 hours to convert the astronomical time into civil time the 17th, 7h 46m A.M.

From the same page of the Almanac take the moon's lower transit for the 17th, 17d 06h 48m, from which subtract the correction 18m for longitude 9 hours east, which gives the moon's lower transit at Nagasaki, and to it add the low water interval, lh 41m, and the result will be the astronomical date and time of low water, 17d 8h llm, and being less than 12 hours is also civil time P.M.

From the same page take the moon's lower transit for the 16th, 160 05h 58m, and from it subtract the correction 18m for longitude 9 hours east, which gives the moon's lower transit at Nagasaki, and to it add the high water interval, 7h 54m, and the result will be the astronomical date and time of high water, 16d 13h 34m. To this add 1 day and subtract 12 hours to convert the astronomical time into civil time the 17th, lh 34m A.M. 18. Example: January 17, 1917. Find the times of high waters and low waters at Nagasaki, Japan.

BY UPPER AND LOWER TRANSITS.

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Moon's upper transit 16th N. A. Cor. for long. gh E. Moon's upper transit Nagasaki High water interval High water (civil time) Moon's upper transit Nagasaki Low water interval Low water (ast. time) Add 1 day and sub. 12 hours Low water (civil time) Moon's lower transit 17th N. A. Cor, for long. gh E. Moon's lower transit Nagasaki Low water interval Low water (civil time) Moon's lower transit 16th N. A. Cor. for long. gh E. Moon's lower transit Nagasaki High water interval High water (ast. time) Add 1 day and sub. 12 hours High water (civil time)

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i High water, 17th 2 Low water, 17th 3 High water, 17th 4 Low water, 17th

Ih 34m A. M. 7 46 A. M. I 59 P. M. 8 II P. M.

BY UPPER TRANSIT.

Moon's upper transit 16th N. A.
Cor. for long. gh E.
Moon's upper transit Nagasaki
High water interval
High water (civil time)
14 lunar day
Low water (civil time)
1/2 lunar day
Low water (ast. time)
Add 1 day and sub, 12 hours
Low water (civil time)
14 lunar day
High water (civil time)

+ +

17

16d 18h 23m

18 16 18 05

7 54 17. ΟΙ

59 P.M. 6 13 08 12 P.M.

I2 26 16

19 46 + 1 -12 17 07 46 A.M.

6 13

+

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1 High water, 17th 2 Low water, 17th 3 High water, 17th 4 Low water, 17th

ih 33m A. M. 7 46

A. M. I 59 P. M. 8 12 P. M.

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