174 
CAPTAIN YOUNGHUSBAND ON PERIODICAL LAWS 
Table IX. 
Mean time at 
Station, 
Astronomical 
St. Helena. i 
Cape of Good Hope. 
Numbers. j 
Values. 
Numbers. 
Values. 
reckoning. 
Easterly. 
— 
Westerly. 
Easterly. 
Westerly. 
Easterly. 
Westerly. . 
Easterly. ; 
Westerly. 
Day. 
19 hours. 
20 
21 
22 
23 
Noon. 
1 
2 
3 
4 
5 
6 
19 
53 
81 
104 
137 
147 
148 
150 
127 
106 
53 
20 
30 
53 
94 
109 
139 
153 
165 
144 
127 
100 
78 
47 
52-6 
160-7 
261-2 
357-5 
479-0 
503-2 
511-0 
515-1 
420-4 
333-4 
158-3 
55-7 
91-7 
171-9 
301-6 
372-3 
481-7 : 
539-2 
589-7 : 
510-8 
436-3 ' 
336-2 ; 
255-1 1 
153-9 
! 
81 ! 
119 
117 
135 
133 
118 
93 1 
80 
48 
33 
22 
22 
83 
129 
136 1 
148 
134 
130 
105 
85 
56 
64 
44 
57 
301-4 
440- 0 
447-9 
533-7 
515-1 
441- 5 
350-3 
287-9 
171-2 
114-1 
66-4 
72-7 
308-1 
440-4 
484-2 
544-6 
510-8 
470-8 
361-3 
289-6 
185-9 
212-9 
161-9 
211-1 
Night. 
7 hours. 
8 
9 
10 
11 
Midnight. 
13 
14 
15 
16 
17 
18 
7 
6 
3 
2 
0 
0 
0 
1 
2 
0 
1 
4 
25 
29 
21 
21 
22 
24 
17 
18 
16 
17 
18 
21 
19-2 
l6-4 
7-8 
5- 1 
0-0 
0-0 
0-0 
2-8 
6- 2 
0-0 
2-5 
12-4 
91-8 
105-8 
89-4 
83-7 
89-9 
96-3 
61-0 
66-6 
50-7 
62-6 
65-9 
77-0 
16 
15 
12 
12 
- 9 
12 
21 
23 
23 
28 
24 
57 
68 
75 
66 
62 
47 
1 45 
j 44 
i 39 
1 33 
36 
32 
67 
46- 2 
42-4 
35-9 
37-6 
31-0 
47- 2 
78-7 
70-6 
76-0 
92-0 
96-8 
229-5 
267-9 
338-6 
271-1 
289-3 
218-7 
199-6 
' 167-8 
166-5 
123-2 
140-0 
115-8 
241-4 
From this table it appears that at St. Helena, although few disturbances occurred 
at night in comparison with those during the day, almost all the nightly disturbances 
were in the westerly direction. During five years of observation 183 disturbances, 
in all, occurred between the hours of 9 p.m. and .5 a.m. inclusive, having a value ot 
690-5 scale divisions ; of these but nine were in the easterly direction with a value ot 
only 24-4 scale divisions, the remaining 174 were in the westerly direction with a 
value of 666-1 scale divisions. During the same number of hours of niaximum 
disturbance, from 9 a.m. to 5 p.m. inclusive, there were 2162 disturbances having a 
value of 7362-0 scale divisions ; of these 1053 were to the east and 1109 to the west, 
the values being 3539-1 and 3822-9 scale divisions respectively; westerly are therefore 
slightly the greater. At the Cape of Good Hope the preponderance of westerly o\ei 
easterly disturbance is greater during the day hours than at St. Helena, and not so 
great during the night hours ; and the analogy with St. Helena is still so far carried 
out that the excess during the night hours is considerably greater than the excess m 
the day hours. 
St. Helena is situated in that part of the globe in which the diurnal movement ot 
the declination needle has peculiar interest. Unlike those places in middle lati- 
