Thread:Tupka217/@comment-28125426-20160817050814/@comment-1013969-20160826133545

Also on the various retcons DC made when Earth-2 became a thing.

The Superman through the ages website explains the difference:

"Although the Earth 2 Superman is portrayed as being the character who appeared in the comics in the '40s, a number of differences exist. Perry White first appears as Clark Kent's boss in Superman #7 in December 1940, although the Earth 2 Superman supposedly never met Perry until after Clark Kent became editor of the Daily Star in the early '50s. The Daily Planet first appears in Superman #4, Spring 1940, with George Taylor as its editor.  In another discrepancy the Earth 2 Luthor is portrayed as red headed, but the bald version of Luthor first appeared in Superman #10, June 1941.

The 1940s Superman also seems to have had a power that the Earth 2 Superman lacks, the ability to use his "super muscular control" to contort his face into any form of disguise that he wishes. This power was first used in Superman #18 and continued to be used through the end of 1947."

You are right about the Golden and Silver Ages having a fuzzy border. It was so bad that the 1948-1958 period is called "Superman in Flux !"

It didn't help that even after DE got the basics down they couldn't make up their minds to the details. For example, in one issue we are shown that Krypton had a space program so extensive it could exile people to other worlds but would then have Jor-El shooting everything into orbit because Krypton didn't have an extensive space program.