284 ME. G-. B. AIET ON THE DIEFEEENCE IN THE MAGNETIC PEOPEETIES 
Experiment 19, March 25, 22^. 
The bars were shifted to the wood of dip plane, with lettered end downwards, and 
were struck heavily with the geological hammer swung out horizontally to arm’s length, 
each bar three times. They were examined immediately. 
Hot-rolled 
longitudinal. 
No. 
Sum. 
Diff. 
readings. 
21 45 
18 25 
17 25 
15 20 
18 15 
15 55 
+ 107 5 
Hot-rolled 
transversal. 
No. 
7 
8 
9 
10 
11 
12 
Diff. 
readings. 
+ 19 40 
+ 19 0 
+ 20 25 
+ 15 30 
+ 16 35 
+ 15 50 
Sum... +107 0 
Cold-rolled 
longitudinal. 
No. 
13 
14 
15 
16 
17 
18 
Sura. 
Diff. 
readings. 
+ 24 55 
+ 26 15 
+ 21 30 
+ 23 25 
+ 22 10 
+ 24 45 
+ 143 0 
Cold-rolled 
transversal. 
No. 
Diff. 
readings. 
19 
+ 28 10 
20 
+ 24 55 
21 
+ 27 3 
22 
+ 26 25 
23 
+ 20 15 
24 
+ 29 10 
Sum... 
+ 156 0 
Total sum . . . +513° 5'. 
The bars were returned to the wood of dip plane, lettered end upwards. 
Experiment 20, March 25, 23*’. 
The bars, on wood of dip plane, lettered end upwards, were struck heavily with the 
geological hammer at arm’s length, each three times. They were then immediately 
placed with lettered end downwards, and struck with blows of similar force, each thi’ee 
times. They were then examined immediately. 
Hot-rolled 
longitudinal. 
No. 
Diff. 
readings. 
1 
+ 
21 
20 
2 
+ 
17 
30 
3 
+ 
16 
15 
4 
+ 
17 
0 
5 
+ 
20 
0 
6 
+ 
17 
35 
Sum... 
+ 109 40 
Hot-rolled 
transversal. 
Cold-rolled 
longitudinal. 
Cold-roUed 
transversal. 
No. 
Diff. 
readings. 
No. 
Diff. 
readings. 
No. 
Diff. 
readings. 
7 
+ 18 50 
13 
+ 25 55 
19 
+ 27 25 
8 
+ 18 30 
14 
+ 24 35 
20 
+ 19 35 
9 
+ 18 10 
15 
+ 24 10 
21 
+ 27 0 
10 
+ 19 25 
16 
+ 24 55 
22 
+ 26 55 
11 
+ 16 40 
17 
+ 25 0 
23 
+ 23 0 
12 
+ 16 30 
18 
+ 26 30 
24 
+ 35 10 
Sura... 
+ 108 5 
Sum... 
+ 151 5 
Sura... 
+ 159 5 
Total sum . . . +527° 55'. 
It is worthy of remark that the diff. reading for the bar No. 20 (8 th in the order of 
examination) at first appeared to be 24° 25'. After examining bar No. 5, bar No. 20 
was again examined, and the diff. readings was found to be 19° 35' as is given above. 
If the first reading was correct (which there is no special reason for doubting), it would 
appear that the bar lost one-fifth part of its magnetism in a few minutes. 
