998 
PROFESSOR J. A, EWING AND MISS H. G. KLAASSEN 
The next three rings had cores of sheet iron. Ring III. was made up of com¬ 
paratively thick annular discs which were turned out of discs that had been supplied 
for the core of a dynamo armature. The mean thickness of the discs was 0‘195 centim.; 
the internal diameter of the annulus was 13*55 centims. and its external diameter 
1545 centims. Rings of paper were interposed to prevent the discs from touching 
one another. The tests showed that this iron compared well with most other 
specimens in the matter of magnetic softness. 
The following cycles were measured :— 
Ring III. — Thick Sheet Iron. 
Cycle (1). 
Cycle (2). 
Cycle (3). 
Cycle (4). 
H. 
B. 
H. 
B. 
H. 
B. 
H. 
B. 
32-34 
15920 
21-60 
14920 
14-62 
13730 
10-42 
12460 
22-51 
15520 
16-66 
14660 
12-19 
13560 
9-11 
12330 
17-23 
15190 
13-59 
14390 
10-44 
13400 
8-12 
12130 
10-10 
14290 
8-73 
13730 
7-29 
12900 
6-08 
11940 
5-97 
13330 
5-47 
12860 
4-86 
12260 
4-33 
11470 
3-30 
12220 
3-08 
11870 
2-09 
10940 
2-70 
10940 
0 
9350 
1-37 
10670 
1-37 
10380 
1-29 
9950 
- 1-33 
5700 
0 
9060 
0 
8950 
0 
8560 
- 1-54 
4180 
- 0-72 
7820 
- 0-95 
7230 
- 0-83 
7100 
- 1-90 
1390 
- 1-33 
5800 
- 1-33 
5630 
- 1-33 
5100 
- 2-28 
- 1060 
- 1-52 
4300 
- 1-52 
4640 
- 1-52 
3720 
- 2-85 
- 3720 
- 1-90 
1390 
- 1-90 
1390 
- 1-90 
660 
- 3-80 
6370 
- 2-28 
- 1190 
- 2-28 
- 1330 
- 2-28 
- 1730 
- 4-75 
7820 
- 2-66 
- 2980 
- 2-66 
- 3120 i 
- 2-66 
- 3580 
- 5-69 
9220 
- 3-04 
— 4440 
- 3-23 
- 4970 
- 3-23 
- 5500 
- 6-65 
10220 
- 3-80 
- 6500 
- 3-80 
- 6570 ! 
- 3-80 
- 6830 
- 7-59 
10870 
- 4-75 
- 8220 
- 4-75 
- 8230 
- 5-69 
- 9550 
- 9-53 
12000 
- 5-69 
- 9290 
- 5-69 
- 9350 : 
- 7-59 
-11010 
-11-30 
12740 
- 7-59 
-10840 
- 7-59 
-11010 
- 8-73 
-11670 
-18-22 
14460 
- 9-49 
-12000 
-10-82 
-12660 
-10-42 
-12460 
-24-15 
15320 
-11-39 
-12770 
-12-15 
-13000 
-25-44 
15460 
-15-18 
-13790 
-14-62 
-13730 
-32-34 
15920 
-18-22 
-14460 
-21-60 
-14920 
