278 ME. a. B. AIEY ON THE DIFFEEENCE IN THE MAGNETIC PEOPEETEES 
placed on the flagstones of the dip plane, with lettered end downwards, and were left 
undisturbed in that state. 
Experiment 6, February 10, 23*’. 
The bars, which had been resting undisturbed on the dip plane with lettered end 
downwards for three days, were taken out for examination without striking or disturb- 
ance. 
Hot-rolled 
longitudinal. 
Hot-rolled 
transversal. 
Cold-rolled 
longitudinal. 
Cold-roUed 
transversaL 
No. 
Diff. 
readings. 
No. 
Diff. 
readings. 
No. 
Diff 
readings. 
No. 
Diff. 
readings. 
1 
O / 
— 16 10 
7 
— 12 35 
13 
— 17 50 
19 
o / 
— 17 40 
2 
— 14 20 
8 
— 14 10 
14 
— 21 10 
20 
— 23 10 
3 
-15 0 
9 
— 14 40 
15 
— 24 20 
21 
— 14 30 
4 
— 8 40 
10 
— 13 40 
16 
— 23 10 
22 
- 17 30 
5 
— 15 30 
11 
— 12 30 
17 
— 19 20 
1 23 
— 23 35 
6 
— 14 20 
12 
-16 0 
18 
— 20 30 
1 24 
- 23 0 
Sum... 
-84 0 
Sum... 
— 83 35 
Sum... 
— 126 20 
Sum... 
— 119 25 
Total sum . . . —413° 20'. 
About ^th part of the magnetism has been destroyed by three days’ exposure to anta- 
gonistic terrestrial magnetism. 
The bars were returned to the dip-plane flagstones in the same position, with lettered 
end downwards. 
Experiment 7, February 11, 0‘*. 
The bars, immediately after the last examination, were returned to the flagstone dip 
plane with lettered end downwards, and each bar was struck once lightly at its centre 
with a joiner’s hammer, weighing with its handle about ^ lb., and were immediately 
examined. 
Hot-rolled 
longitudinal. 
Hot-roUed 
transversal. 
Cold-rolled 
longitudinal. 
Cold-roUed 
transversal. 
No. 
Diff. 
readings. 
No. 
Diff. 
readings. 
No. 
Diff. 
readings. 
No. 
Diff 
readings. 
1 
+ 12 10 
7 
+ 16 10 
13 
o / 
+ 90 
19 
O / 
+ 17 0 
2 
-)-ll 40 
8 
-1-15 30 
14 
+ 15 0 
20 
+ 11 20 
3 
-fl5 20 
9 
+ 12 0 
15 
+ 13 10 
21 
+ 16 30 
4 
-1-8 0 
10 
+ 11 0 
16 
+ 8 20 
22 
+ 9 40 
5 
-1-12 10 
11 
+ 10 15 
17 
+ 16 10 
23 
+ 8 40 
6 
-1-12 40 
12 
+ 10 40 
18 
+ 15 30 
24 
+ 5 40 
Sum... 
+ 72 0 
Sum... 
+ 75 35 
Sum... 
+ 77 10 
Sum... 
+ 68 50 
Total sum . . . -4-293° 35'. 
The light blow has destroyed the former magnetism, and has given an opposite 
magnetism of nearly three-fourths its amount. 
