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BELL SYSTEM TECHNICAL JOURNAL 



Plate III. Apparatus assembly. 



T 



A — ^Amplifier 

 B — Batteries 

 C — Camera 

 P-T-Calibration Set 

 / — Integrator 

 M — Magnetizing Coil 

 O — Oscillograph Tube Box 

 P— Power Unit 

 5 — Sample 

 T — Tension Rack 



