Towns > Glasgow > 1828-1912 - Post-Office annual Glasgow directory > 1853-1854

22
ELUCIDATION OF THE PRECEDING TABLES.
Required the time of the sun's rising and setting at Glasgow, in latitude 55° 52' N.,
longitude 4° 16' W., on May 20, 1854.
The approximate time of the sun's rising and setting is —
Rising, 3 h. 50 m. Setting, 8 h. 10 m.
Longitude of time in Glasgow -f- W -J- 17
4 7 8 27
The sun's decimation reduced to these times is 19° 54' and 20° 3', and the polar
distances are 70° 6' and 69° 57'. The horizontal refraction, less sun's parallax, is
34' 17—9" = 34' 8" + 90 = 90° 34' 8", and hence the following computation: —
Zenith, distance, 90°
34'
90°
34'
Polar distance,.. 70
06
co-secant 0.026739 69
57
co-secant 0.027152
08
co-secant 0.250944 34
8
co-secant 0.250944
194
48
194
39
97
24
sine 9.996368 97
19i
sine 9.996441
6
50
sine 9.075480 6
45
sine 9.070176
-^ 2)19.349531
-f- 2)19.344713
sine 9.674765
co-sine 9.672356
H.
M. S.
H. M. S.
1
52 53
2
4 7 48
2
Equa. time,.
3 45 46
3 47
Equa. time,
8 15 36
3 45
Time of Rising, 3 42
Time of setting,.... 8 11 51
Note. — The latitude of Glasgow is 55° 52' north, the longitude 4° 16' west of
Greenwich ; consequently there are 17 minutes of difference of time between the clocks
of Greenwich and the clocks at Glasgow, the Greenwich time being earlier. The
clocks of the United Kingdom are now generally adjusted to Greenwich time.
JAMES YUILLE,
Teacher of Mathematics, Navigation, and Nautical Astronomy,
56 Jamaica Street, Glasgow.