528 
]\[R. A. W. RUCKER AND DR. T. E. THORPE ON A MAGNETIC 
Table XIII. 
s 
o 
Stations. 
Interval 
in 
years. 
Secular change in five 
year’s in 
Mean secular change in 
five years in 
Mean 
Latitude ; 
and 
Longi¬ 
tude. 
Declina¬ 
tion. 
Dip. 
Horizontal 
force. 
Declina¬ 
tion. 
Dip. 
Horizontal 
force. 
A 
Lairg. 
Golspie. 
Thurso. 
Wick. 
G-94 
G'96 
G-99 
6-99 
-34-G 
-37-6 
-41-5 
-38-4 
- 3-0 
- 31 
- 4-9 
- 6-9 
+ •0060 
85 
95 
115 
/ 
-38-0 
i 
-4-5 
+ ■0089 
O 1 
58 15 ■ 
•3 45 
1 
i 
1 
B 
Kyle Akin .... 
Gairloch .... 
Soa. 
7-88 
7-89 
7-91 
-4’2-4 
-26-6 
-41-3 
- 3-3 
- 4T 
- 3-4 
79 
57 
113 
-3G-8 
-3-6 
83 
57 23 1 
5 52 j 
c 
1 
1 
Mablethorpe . 
Lincoln . 
Gainsborough . 
G-27 
4'35 
4-93 
-34-5 
— 28'G 
-31-6 
- 3T 
- G-7 
- 6-6 
89 
76 
98 
-31-6 
5'5 
88 
53 19 
0 20 
D 
1 
Oxford. 
St. Leonards . 
Salisbury .... 
Tunbridge Wells . 
6-30 
5- 74 
6- 00 
4-59 
-33-4 
-28-8 
-33-4 
— 35’5 
- 4-4 
- 5T 
- 5-3 
- 3T 
34 
80 
56 
96 
-32*8 
—-i'S 
67 
i 
51 12 i 
0 34 1 
1 
E 
.4.rmagh. 
Enniskillen 
Sligo. 
Carrick-on-Slianiiuii 
4'8G 
4- 78 
5- 09 
509 
-40-4 
-42-9 
-38-8 
-41-5 
- 5-0 
- 6-4 
- 7-4 
- 2-3 
139 
127 
101 
97 
-40-9 
116 
54 14 
7 43 
P 
G 
Swansea .... 
Cardiff ... 
Milford . . . 
5-97 
5'96 
4-81 
-39-0 
-34-3 
-40-8 
- 6-3 
- GT 
- 5-9 
104 
119 
97 
-38-0 
-6-1 
107 
1 
51 36 
4 2 
Charle^dlle .... 
Kiilai'ney .... 
Bantry. 
Valentia .... 
483 
4-81 
4-81 
4-00 
-35T 
-.38-9 
-40-7 
-47-3 
- 8-7 
- G-6 
-10-2 
- 4'5 
151 
115 
120 
GO 
-40-5 
— 7‘5 
112 
52 0 
9 30 
The differences between these results are certainly in some cases mnch larger than 
can be accounted for by a mere accumulation of the errors of experiment. The results 
obtained in the two surveys at Spalding were so obviously discrepant that we have 
not used them in the calculation of the secular change. 
At Lairg, Gairloch, and Valentia the earlier and later observations were made_ at 
different places, which may account for the results at these stations being abnormal. 
In the North of Scotland they are elsewhere as good as the nature of the ground 
