[tz] The Mysterious Cube

[Paul Eggert]

Thanks, I installed that patch into the experimental version on GitHub.

Wow, the Arlington Time Signal -- it's been a looong time since that phrase was 
in common use.  Although a big deal in the early days of radio, the Arlington 
Radio Towers were dismantled in 1941 because they would have been a hazard to 
aircraft approaching the new Washington National Airport; see 
<http://www.waymarking.com/waymarks/WMDEB_The_Arlington_Radio_Towers>.

Perhaps the 1957 Superman episode was derived from an earlier source, a comic 
book say?  Or maybe Superman had some time-travel powers that "The Mysterious 
Cube" didn't disclose....