or HOT-EOLLED AJS'D COLD-EOLLED MALLEABLE lEON. 
287 
These results appear to leave no doubt that, as a general rule, the cold-rolled iron 
will, under similar circumstances, take up a heavier charge of magnetism than the hot- 
rolled iron, in the proportion of 545 : 455, or 1’2 : 1'O, very nearly. It also appears that 
the cold-rolled longitudinal takes a heavier charge than the cold-rolled transversal. 
The departures from this result, in Experiments 8, 9, 10, 14, are confined to small 
charges of magnetism, in which accident might have greater play. They are also con- 
fined to magnetism of -f- character ; of this, perhaps, the following is the explanation. 
The bars when received from the manufacturer had + magnetism (see Experiments 1 
and 2). It would seem therefore that the hot-rolled bars differ from the cold-rolled 
bars in this particular, that the hot-rolled bars retain rather more of their primitive 
magnetism, under all changes, than the cold-rolled bars retain. 
III. Proportions of the Aggregate of Magnetism, without regard of sign, carried by the 
different classes of Bars, when they have been struck while lying with tendency 0. 
Hot-rolled 
longitudinal. 
Hot-rolled 
transversal. 
Cold-rolled 
longitudinal. 
Cold-rolled 
transversal. 
Experiment 3. 
•184 
•464 
•157 
•193 
11. 
•102 
•106 
•638 
•154 
12. 
•178 
•220 
•457 
•145 
18. 
•380 
•264 
•282 
•073 
Mean 
•211 
•264 
•384 
•141 
I do not attach great importance to the apparent tendency of the cold-rolled longi- 
tudinal bars to retain much magnetism and of the cold-rolled transversal bars to retain 
little. The observed deviations are small, and a trifling accidental error may materially 
disturb the results. 
TV. Spontaneous Losses of Magnetism in the Bars of different Classes, when they have 
rested undisturbed. 
Hot-rolled 
longitudinal. 
Hot-rolled 
transversal. 
Cold-rolled 
longitudinal. 
Cold-rolled 
transversal. 
Sum. 
Exp. 1 to 2, 1 day, tendency 0 
5 to 6, 3 days, tendency +, opposing 
7 to 8, 1 day, +, favouring 
9 to 10, 3 days, 0 
15 to 16, 30 days, 0 
20 to 21, 1 day, — , opposing; 4 days, 0 ... 
5 25' 
31 20 
3 40 
19 50 
22 10 
23 35 
0 t 
11 10 
25 25 
10 50 
18 45 
26 15 
19 20 
8 0 
28 35 
4 40 
32 15 
27 30 
29 45 
2 5.5 
22 17 
2 10 
12 30 
20 35 
17 15 
27 30 
107 37 
21 20 
83 20 
96 30 
89 55 
Sura 
106 0 
111 45 
130 45 
77 42 
426 12 
