THE COMPASS-MIEDLE ON THE DEVIATIONS OE THE COMPASS. 
179 
Appkndix IL 
Experiments, Magnet Endways. (Plate V.) 
Compass -needles placed on a fixed pivot in centre of re- 
volving table; south pole of a 12-inch bar magnet placed 
18‘25 inches from the pivot, 2‘75 inches below its level. 
Compass -needles placed on a fixed pivot in 
centre of revolving table; south pole of a 
12-inch bar magnet placed 18 inches from 
the pivot, I inch below level. 
Magnetic direction, 
of point opi^osite 
bar magnet. 
Deviation of Compound needles. 
3f inches. 
7-^ inches. 
North. 
1 6 w. 
o / 
0 0 
N by E. 
15 35 „ 
15 55 W. 
N.N.E. 
25i 50 „ 
27 55 „ 
N.E. 
36 10 „ 
36 55 „ 
E.N.E. 
34 30 „ 
35 55 „ 
East. 
29 50 „ 
31 10 „ 
E.S.E. 
22 30 „ 
24 15 „ 
S.E. 
15 50 „ 
16 35 „ 
S.S.E. 
8 5 „ 
8 30 „ 
South. 
0 10 E. 
0 0 
S.S.W. 
8 20 „ 
8 30 E. 
s.w. 
15 35 „ 
16 40 „ 
w.s.w. 
24 10 „ 
2-1. 5 „ 
West. 
30 20 „ 
31 15 ;, 
W.N.W. 
35 50 „ 
35 40 „ 
N.W. 
36 20 „ 
36 40 „ 
N.N.W. 
26 20 „ 
27 10 „ 
N by W. 
l6 35 „ 
16 25 „ 
Magnetic direction 
of point opposite 
bar magnet. 
Deviation of Single needles. 
3 inches. 
6 inches. 
12 inches. 
O / 
O f 
North. 
0 0 
0 10 E. 
2 50 E. 
N by E. 
12 20 W. 
14 0 W. 
22 30 W. 
N.N.E. 
20 55 „ 
22 15 „ 
25 25 „ 
N.E. 
29 45 „ 
29 5 „ 
25 55 „ 
E.N.E. 
30 35 „ 
30 0 „ 
26 10 „ 
East. 
27 20 „ 
27 35 „ 
27 50 „ 
E.S.E. 
21 55 „ 
22 55 „ 
27 10 „ 
S.E. 
14 50 „ 
16 15 „ 
20 45 „ 
S.S.E. 
7 30 „ 
8 25 „ 
10 50 „ 
South. 
0 0 
0 0 
0 0 
S.S.W. 
7 50 E. 
8 15 E. 
11 0 E. 
S.W. 
14 55 „ 
15 40 „ 
20 15 „ 
w.s.w. 
21 25 „ 
22 0 „ 
26 5 „ 
W’ est. 
26 30 „ 
26 40 „ 
26 45 „ 
W.N.W. 
29 10 „ 
28 30 „ 
25 20 „ 
N.W. 
28 30 „ 
27 50 „ 
25 30 „ 
N.N.W. 
20 30 „ 
21 55 „ 
25 10 „ 
N by W. 
12 10 „ 
14 5 „ 
22 30 „ 
Note. — These experiments were arranged to represent the deviation of an iron ship having a negative semi- 
circular deviation. 
Experiments, Magnet Sideways. (Plate V.) 
Compass-needles placed on a fixed pivot in centre of re- 
volving table ; a 12-inch bar magnet placed on the table 
at right angles to the line drawn from its centre to the 
pivot; the distance from tlie centre to the pivot 19*75 
inches, and on same level. 
Magnetic direction 
of neutral line. 
Deviation of Single needles. 
3 inches. 
G inches. 
12 inches. 
O ! 
O / 
North. 
1 0 w. 
0 45 W. 
0 0 
N.N.E. 
5 0 E. 
4 45 E. 
1 45 E. 
N.E. 
11 10 „ 
10 15 „ 
6 10 „ 
E.N.E. 
17 5 „ 
16 40 „ 
13 55 „ 
East. 
22 20 „ 
22 50 „ 
23 10 „ 
E.S.E. 
25 15 „ 
27 0 „ 
33 0 „ 
S.E. 
24 5 „ 
25 30 „ 
34 20 „ 
S.E by S. 
21 0 „ 
20 30 „ 
12 50 „ 
S.S.E. 
16 0 „ 
13 50 „ 
5 10 „ 
South. 
1 50 E. 
2 0 E. 
2 5 E. 
S.S.W. 
12 40 W. 
10 0 W. 
0 0 
S.W by S. 
18 50 „ 
17 30 „ 
5 45 W. 
S.W. 
23 0 „ 
24 15 „ 
40 0 „ 
W.S.W. 
25 30 „ 
27 45 „ 
36 0 „ 
West. 
23 15 „ 
23 55 „ 
25 25 „ 
W.N.W. 
18 35 „ 
17 55 „ 
15 5 „ 
N.W. 
13 0 „ 
11 50 „ 
6 50 „ 
N.N.W. 
7 0 „ 
5 50 „ 
1 40 „ 
Compass-needles placed on a fixed pivot in 
centre of revolving table; a 12-inch bar 
magnet placed on the table at right angles 
to the line drawn from its centre to the 
pivot; the distance from the centre to the 
pivot 17 inches, and on same level. 
Magnetic direction 
Deviation of Compound needles. 
of neutral line. 
■3f inches. 
7^ inches. 
North. 
0 30 E. 
6 30 E. 
N.N.E. 
8 50 „ 
8 50 „ 
N.E. 
17 0 „ 
17 0 „ 
E.N.E. 
24 30 „ 
24 10 „ 
East. 
32 0 „ 
30 0 „ 
E.S.E. 
36 0 „ 
33 50 „ 
S.E. 
37 25 „ 
35 30 „ 
S.S.E. 
30 30 „ 
32 10 „ 
S by E. 
18 45 „ 
26 15 „ 
South. 
3 0 E. 
6 40 E. 
S by W. 
14 35 W. 
21 45 W. 
S.S.W. 
27 30 „ 
30 50 „ 
s.w. 
3.3 40 „ 
36 0 „ 
w.s.w. 
33 40 „ 
35 0 ,, 
West. 
30 0 „ 
30 40 „ 
W.N.W. 
23 50 „ 
24 30 „ 
N.W. 
16 30 „ 
17 0 „ 
N.N.W. 
8 10 „ 
8 20 „ 
2 c 2 
