Postcards: I believe I have nearly 100 (though most are new ones I picked up on my travels).
Books: Catholic school readers from the ‘50’s (this is almost all I read growing up - and loved them), music books, and of course histories.
Photographs: Mostly of my family but I love finding others as well.
I’m sure there’s other categories but that’s all I can think of off the top of my head

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From left to right:
Earlier picture of my postcards
Book of organ music circa 1870
Elementary history book copyright 1898
High school religion textbook copyright 1946