918 



THE BELL SYSTEM TECHNICAL JOURNAL, OCTOBER 1951 



T = 2600° K V = 



10 SECONDS ^ 



V=9230, L = 17/tA 



V5 SECOND 



T = 1600° K V = O 



20 MINUTES 



V= 9220,^ L=18AtA 



V5 SECOND 



T =2400°K V = 



3 MINUTES 



V=9230 i = ]7fiA 



1/5 SECOND 



1200° K V 



20 MINUTES 



9170 L=:23.2/tA 



1/5 SECOND 



T = 2000° K 



20 MINUTES 



V = 9220 l=\e/iA 



1/5 SECOND 



T = 2400° K V = 

 3 MINUTES 



V=9230 L=16.8/tA 



1/5 SECOND 



Fig. 4 — Effect of temperature on size and shape of principal planes for clean W. 



