Need Identification Guide For Antique Covers

Beautiful covers! and a huge source of history.
Al E Gator, that's the sort of album page I do for my covers as well. Social Postal History is a great pursuit and a fascinating way to connect these old pieces of paper with real people. Remember, these were from the days waaaaaaay before the internet and instant messaging. We get responses in minutes if not seconds. These folks sometimes waited months or years to receive a long desired letter. They were precious things!