up test for Dick Van Dyke in the  projection room, Walt Disney (qv) saw Van Dyke entertaining crew  members on the test film between between takes with some comic  routines, among them the "stepping down" routine of an old man  trying to step off a curb without hurting himself. The test film not  only convinced Disney to cast Dick Van Dyke as Mr. Dawes, Sr., but  Walt specifically requested that crew members "build a six