[perl4ever]

I remember seeing a thick dead tree type of book with the history of time zones in the US, for figuring out times in historical documents when things were less standardized. It was practically the size of a phone book; I think it probably covered county level history or something like that.

[macintux]

I have a book covering, among other things, Indiana time zones for a few years during IIRC the 1960s.

It’s frankly amazing how much they changed every year. Different counties, and sometimes towns/cities within counties, would jump back and forth year to year. It would have been awful to manage if computers had been more important at that time.