98 
MR. AIRY ON THE OBSERVED DEVIATIONS OF THE COMPASS 
Table of Polar-Magnet-Deviations, 
Apparent Azimuth from Neutral 
Position 
n points and decimals. 
Modulus. 
•70 
•71 
•72 
•73 
•74 
•76 
•76 
•77 
•78 
•79 
•80 
Corresponding Polar-Magnet-Deviation, in degrees and minutes. 
-f 
-f- 
- 
- 
P 
P 
P 
P 
o 
/ 
o 
/ 
o 
/ 
o 
/ 
O 
/ 
O 
/ 
o 
/ 
o 
/ 
O 
/ 
O 
/ 
O 
/ 
0-0 
16-0 
16-0 
32-0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0-1 
15-9 
16-1 
31-9 
0 
47 
0 
47 
0 
48 
0 
48 
0 
49 
0 
50 
0 
51 
0 
31 
0 
52 
0 
53, 
0 
54 
0-2 
15-8 
16-2 
31-8 
1 
34 
1 
35 
1 
CO 
1 
38 
1 
40 
1 
41 
1 
43 
1 
44 
1 
45 
1 
46 
1 
48 
0-3 
15-7 
16-3 
31-7 
2 
21 
2 
23 
2 
25 
2 
27 
2 
29 
2 
31 
2 
34 
2 
36 
2 
38 
2 
40 
2 
42 
0-4 
13-6 
16-4 
31-6 
3 
8 
3 
11 
3 
14 
3 
16 
3 
19 
3 
22 
3 
25 
3 
27 
3 
30 
3 
33 
3 
36 
0-5 
13-3 
16-3 
31-3 
3 
56 
3 
59 
4 
2 
4 
5 
4 
9 
4 
12 
4 
16 
4 
19 
4 
23 
4 
26 
4 
30 
0-6 
13-4 
16-6 
31-4 
4 
43 
4 
47 
4 
51 
4 
53 
4 
59 
5 
3 
5 
8 
5 
12 
5 
16 
5 
20 
5 
24 
0-7 
13-3 
16-7 
31-3 
3 
30 
5 
34 
5 
39 
5 
44 
5 
49 
5 
54 
5 
59 
6 
3 
6 
8 
6 
13 
6 
18 
0-8 
13-2 
16-8 
31-2 
6 
17 
6 
22 
6 
28 
6 
33 
6 
39 
6 
44 
6 
50 
6 
55 
7 
1 
7 
6 
7 
12 
0-9 
13-1 
16-9 
31-1 
7 
4 
7 
1 
7 
16 
7 
22 
7 
28 
7 
34 
7 
41 
7 
47 
7 
53 
7 
59 
8 
6 
1-0 
13-0 
17-0 
31-0 
7 
31 
7 
57 
8 
4 
8 
11 
8 
18 
8 
25 
8 
32 
8 
38 
8 
45 
8 
52 
8 
59 
1-1 
14-9 
17-1 
30-9 
8 
38 
8 
45 
8 
52 
8 
59 
9 
i 
9 
15 
9 
23 
9 
30 
9 
38 
9 
45 
9 
53 
1-2 
14-8 
17-2 
30-8 
9 
24 
9 
32 
9 
40 
9 
48 
9 
56 
10 
4 
10 
13 
10 
21 
10 
29 
10 
37 
10 
46 
1-3 
14-7 
17-3 
30-7 
10 
10 
10 
19 
10 
28 
10 
37 
10 
46 
10 
35 
11 
4 
11 
13 
11 
22 
11 
31 
11 
40 
1-4 
14-6 
17-4 
30-6 
10 
57 
11 
6 
11 
16 
11 
25 
11 
35 
11 
45 
11 
55 
12 
4 
12 
14 
12 
23 
12 -33 
1-5 
14-3 
17-5 
30*3 
11 
43 
11 
53 
12 
4 
12 
14 
12 
24 
12 
34 
12 
43 
12 
53 
13 
5 
13 
15 
13 
26 
1-6 
14’4 
17-6 
30-4 
12 
29 
12 
41 
12 
51 
13 
2 
13 
13 
13 
24 
13 
35 
13 
46 
13 
57 
14 
8 
14 
19 
1-7 
14-3 
17-7 
30-3 
13 
15 
13 
27 
13 
39 
13 
50 
14 
2 
14 
14 
14 
26 
14 
37 
14 
49 
15 
0 
15 
12 
1-8 
14-2 
17-8 
30-2 
14 
1 
14 
13 
14 
26 
14 
38 
14 
50 
15 
0 
15 
15 
15 
27 
15 
39 
15 
52 
16 
4 
1-9 
14T 
17-9 
30-1 
14 
47 
15 
0 
15 
13 
15 
26 
15 
39 
15 
52 
16 
5 
16 
18 
16 
31 
16 
44 
16 
57 
2-0 
14-0 
18-0 
30-0 
13 
32 
15 
45 
15 
59 
16 
12 
16 
26 
16 
40 
16 
54 
17 
8 
17 
22 
17 
35 
17 
49 
2-1 
13-9 
18-1 
29-9 
16 
17 
16 
31 
16 
46 
17 
0 
17 
15 
17 
29 
17 
44 
17 
58 
18 
13 
18 
27 
18 
42 
2-2 
13-8 
18-2 
29-8 
17 
2 
17 
17 
17 
32 
17 
47 
18 
2 
18 
17 
18 
33 
18 
48 
19 
3 
19 
18 
19 
34 
2-3 
13-7 
18-3 
29-7 
17 
47 
18 
2 
18 
18 
18 
34 
18 
50 
19 
6 
19 
22 
19 
38 
19 
54 
20 
10 
20 
26 
2-4 
13-6 
18-4 
29-6 
18 
31 
18 
47 
19 
4 
19 
20 
19 
37 
19 
34 
20 
11 
20 
27 
20 
44 
21 
1 
21 
18 
2-3 
13-3 
18-3 
29-5 
19 
16 
19 
33 
19 
50 
20 
7 
20 
25 
20 
42 
21 
0 
21 
17 
21 
35 
21 
52 
22 
10 
2-6 
13-4 
18-6 
29-4 
20 
0 
20 
18 
20 
36 
20 
54 
21 
12 
21 
30 
21 
49 
22 
7 
22 
25 
22 
43 
23 
1 
2-7 
1.3-3 
18-7 
29-3 
20 
44 
21 
2 
21 
21 
21 
40 
21 
59 
22 
18 
22 
37 
22 
55 
23 
14 
23 
33 
23 
52 
2-8 
13-2 
18-8 
29-2 
21 
27 
21 
46 
22 
6 
22 
25 
22 
43 
23 
5 
23 
23 
23 
44 
24 
4 
24 
23 
24 
43 
2-9 
13-1 
18-9 
29-1 
22 
10 
22 
30 
22 
51 
23 
11 
23 
31 
23 
51 
24 
12 
24 
32 
24 
52 
25 
12 
25 
33 
3-0 
13-0 
19-0 
29-0 
22 
53 
23 
14 
23 
35 
23 
56 
24 
17 
24 
38 
24 
59 
23 
20 
25 
41 
26 
2 
26 
23 
3-1 
12-9 
19-1 
28-9 
23 
36 
23 
57 
24 
19 
24 
40 
25 
2 
25 
24 
25 
46 
26 
H 
l 
26 
29 
26 
51 
27 
13 
3-2 
12-8 
19-2 
28-8 
24 
18 
24 
40 
23 
2 
25 
24 
25 
47 
26 
9 
26 
32 
26 
54 
27 
17 
27 
39 
28 
2 
3-3 
12-7 
19-3 
28-7 
23 
0 
25 
22 
25 
45 
26 
8 
26 
32 
26 
55 
27 
19 
27 
42 
28 
5 
28 
28 
28 
52 
3-4 
12-6 
19-4 
28-6 
23- 
41 
26 
4 
26 
28 
26 
32 
27 
16 
27 
40 
28 
5 
28 
29 
28 
53 
29 
17 
29 
41 
3-5 
12-3 
19-3 
28-3 
26 
22 
26 
46 
27 
10 
27 
35 
28 
0 
28 
25 
28 
50 
29 
15 
29 
40 
30 
5 
30 
30 
3-6 
12-4 
19-6 
28-4 
27 
3 
27 
27 
27 
52 
28 
17 
28 
43 
29 
9 
29 
35 
30 
0 
30 
26 
30 
52 
31 
18 
3-7 
12-3 
19-7 
28-3 
27 
43 
28 
8 
28 
34 
29 
0 
29 
27 
29 
53 
30 
20 
30 
46 
31 
13 
31 
39 
32 
6 
3-8 
12-2 
19-8 
28-2 
28 
22 
28 
48 
29 
15 
29 
42 
30 
9 
30 
36 
31 
4 
31 
31 
31 
58 
32 
25 
32 
53 
3-9 
12-1 
19-9 
28-1 
29 
1 
29 
28 
29 
56 
30 
24 
30 
52 
31 
20 
31 
48 
32 
16 
32 
44 
33 
12 
33 
40 
4-0 
12-0 
20-0 
28-0 
29 
40 
30 
8 
30 
37 
31 
5 
31 
34 
32 
2 
32 
31 
33 
0 
33 
29 
33 
58 
34 27 
-f 
I + 
