114 
LIEUT.-COLONEL SABINE ON TERRESTRIAL MAGNETISM. 
te October 13th. Needle 5. 
Times. 
Temp. 
Diffs. 
Spare Magne- 
tometer. 1. Sc. 
Div. = 1'00. 
Declination Magnetometer. 
1. Sc. Div. = 0'-698. 
Bifilar Magnetometer. 
Jc = -00016 : q = -00016 approx. 
Readings. 
Corrected 
Readings. 
Diffs. 
Readings. 
Temp. 
Corrected 
Readings. 
Diffs. 
h m 
Sc. Div. 
Sc. Div. 
Sc. Div. 
Sc. Div. 
Sc. Div. 
Sc. Div. 
Sc. Div. 
21 40 
250-5 
42-7 
42-7 
22 3 
54-0 
249-8 
228-8 
229-3 
186-6 
180-9 
54-3 
180-9 
56 
92-0 
38-0 
248-3 
225-3 
226-8 
2-5 
179-5 
55-0 
180-2 
+ 0-7 
23 26 
56-2 
35-8 
246-1 
226-7 
229-8 
3-0 
179-0 
55-3 
180-0 
— 0-2 
47 
86-0 
29-8 
245-0 
223-5 
227-3 
2-5 
179-2 
55-7 
180-6 
-0-6 
24 00 
56-5 
29'5 
243-0 
224-3 
229-5 
2-2 
179-7 
56-0 
181-4 
+ 0-8 
4)133-1 
10-2 
+ 0-7 
33-3 
2-55 
+ 0-2 
2-55 
, 0-2 x 
•00016 
— n*M( i 
3 33-3 x 186-6 ' 33-3 
October 22nd. 
Needle 5. 
22 21 
238-8 
1703-6 
1703-6 
34 
66-4 
238-0 
1586-2 
1586-8 
116-8 
190-6 
45-3 
190-6 
56 
90-7 
44-3 
237-3 
87-9 
89-0 
2-2 
190-5 
46-0 
191-2 
-0-6 
0 18 
58-0 
32-7 
235-3 
85-3 
87-7 
1-3 
191-2 
47-0 
192-9 
+ 1-7 
38 
75-1 
17-1 
234-8 
85-6 
88-4 
0-7 
192-1 
47-7 
194-5 
-1-6 
57 
54-9 
20-2 
234-6 
84-0 
86-9 
1-5 
193-7 
48-5 
196-9 
+ 2-4 
4)114-3 
5-7 
+ 1-9 
28-6 
1-425 
+ 05 
a — 
1-425 
0-5 x -00016 _ 0 . 00042 g 6 
+ 0-000003 = 0-00043. 
* 28-6 x llb-8 
28-b 
“ The ‘ readings’ are the means, each, of three or four separate readings, at intervals 
of two or three minutes. 
“ Similar series were observed with eight other needles; the approximate results 
for each needle are as follows : — 
Date. 
No. of Needle. 
Value of q. 
Means. 
October 14. 
22. 
5 
5 
0-00041 
0-00043 J 
0-00042 
14. 
November 22. 
6 
6 
0-00056 ] 
0-00074 
0-00065 
22. 
24. 
7 
7 
0-000090) 
0-000017J 
0-00005 
26. 
8 
0-00014 
0-00014 
26. 
9 
0-00012 
0-00012 
26. 
10 
0-00009 
0-00009 
28. 
11 
0-00019 
0-00019 
28. 
12 
0-00014 
0-00014 
29. 
13 
0-00022 
0-00022 
