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BELL SYSTEM TECHNICAL JOURNAL 



required lo study or eliminate the effects of eddy-currents, demagnetizing 

 lields and directional effects and to simulate the use of material in apparatus. 

 Most of the needs arizing in commerce and in experimental investigation 

 are filled by strips or sheets of thicknesses from 0.002 inch to 0.1 inch from 



(a) 4-HIGH MILL, SIDE VIEW 



(b) 4-HIGH MILL, END VIE\, 



(C) 20-HIGH ROHN MILL {d)l2-HIGH SENDZIMIR MILL 



Fig. 14 — Arnmgement of rolls ia mills used for reduction of ihin sheet: (a) and (h) con- 

 ventional 4-high mill; (c) Rohn 20-high; (d) Sendzimir 12-high. 



which coils can be wound or parts cut, by rods from which relay cores or 

 other forms can be made, by powdered material used for pressing into cores 

 for coils for inductive loading, and by castings for permanent magnets or 

 other objects which may be machined or ground to final shape. 



