The American flag adorning the child's sand castle has its stars arranged in the staggered rows of 5 and 6 stars as in the current 50 stars arrangement. An American flag of the 1920's would have had its stars in the 6 rows of 8 arrangement.
As Nicole and Dick walk along Lindenhof Hill above Zurich in the early 1920s, the background view of the city shows several concrete apartment blocks not built until the 1950s.