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BELL SYSTEM TECHNICAL JOURNAL 



Plate I. Hysteresis curves of iron and permalloy under various conditions. 



1. Armco iron at various fields. 



2. Permalloy at (o) 25", {h) 200", (c) 1,000'; high field. 



3. Armco iron at (a) 25", (6) 200", (c) 1,000"; low field. 



4. Armco iron (a) and 78 per cent permalloy (5); high field. 



5. Armco iron (a) and 78 per cent permalloy (6); low field. 



6. 65 per cent permalloy, (a) without tension, {b) with tension. 



