“…( 4 5) In the majority of cases, e.g. 4340 steel in cadmium (46) and Cu-2%e in mercury (47), readily recognizable delayed failure (type A behavior) was observed, but in several instances, all involving mercury or mercury-indium environments on zinc (48), cadmium (48), silver (49), or aluminum (49), delayed failure did not occur (type B behavior). In type 3 situations, there appears to be a critical stress above which failure is virtually "instantaneous" (less than 1-2 sec) but below which no failure is observed.…”