horizontal needle when under the influence of magnets. 385 
2 0 58'; and for No. II, 5 0 3 5' and 1 °55*- The effects after- 
wards corresponded with these, but they will be best under- 
stood from the observations themselves. 
Compass No. I. May 18 . 
Time. 
Points of Equilibrium. 
Remarks* 
N. W. 
N. E. 
S. E. 
h. m. 
O » 
0 'o 
0 / 
5 15 
80 40 
79 3 8 
0 52 
6 00 
72 36 
72 46 
1 06 
7 00 
67 20 
67 50 
1 1 6 1 
Clear sun, striking hot upon the 
8 co 
62 38 
63 04 
1 08 1 
magnets. 
9 00 
64 26 
64 48 
1 00 ‘ 
The magnets somewhat sheltered 
10 00 
65 36 
65 42 
0 52 1 
by trees. 
11 00 
52 28 
50 56 
1 04 
The magnets had become hot. 
Noon. 
45 22 
44 i 6 
0 42 
1 00 
49 32 
49 H 
0 06 W. 
Sun obscured. 
2 00 
50 26 
50 24 
0 18 E. 
3 00 
51 26 
5 1 34 
0 32 
4 00 
51 52 
51 48 
0 30 
Sun faintly out. 
5 00 
53 2 ° 
53 2 4 
0 30 
6 00 
54 00 
54 06 
0 26 
7 00 
54 2 ° 
54 3 ° 
0 32 
I 
8 00 
55 4 ° 
55 5 ° 
0 36 
\ 
Cold evening. 
9 00 
56 20 
56 28 
0 38 . 
I 
Comparing the changes here with those of the day before, 
we have : 
From the morning till the 1 
middle of the day - j 
From the middle of the day 1 
till night - j 
Changes of direction. 
May 1 8. 
May 17. 
W. point. 
E. point. 
S. point 
W. point. 
E. point. 
S. point. 
0 / 
35 18 
io 58 
0 , 
35 22 
12 12 
0 # 
I 22 
0 44 
3 5 6 
8 04 
0 » 
4 26 
8 28 
0 / 
c 44 
0 40 
The effect produced on the magnets by the heat of the sun 
appears to have been of a permanent character, since, although 
MDCCCXXIII. 3 D 
